Troubleshooting
Find what you see in the first column. Most fixes are a setting or a re-run, not a new method.
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Version 1 (2026-10-15): the same steps as this page, with every download’s link and checksum. sha256 7338cb285c3010710ec59b6924eb5df71870e94d414e73ef682fd11c473197e2, also in the manifest.
The picture
| You see | Why | Fix |
|---|---|---|
| The replaced area is solid black | An old ComfyUI build: the plain 0.37.0 release with older Python packages returned black frames | Install the ComfyUI release the guides name, in a new folder (version) |
| The new creature looks like the old one | The shot went in as a reference video: it pins the old design | Rebuild a shot: use the full-frame file without a reference video. Rebuild with actors: grey the old creature out in the reference (the blank-reference file); check the mask covers it on every frame |
| The old place comes back (Rebuild with actors, a new place) | The reference video still showed the old set, or the shot’s depth rebuilt it | Grey the background in the reference (the people masks' background output). Control end 0.6 for medium shots (with a soft close crop as Picture 1), 0.25 for close-ups and two-shots |
| A fast creature against a dark background comes out pale or white | The redraw lost the creature’s color against the dark | Try a new seed; if it’s still pale, keep the original shot (in our test, 4 of 12 shots stayed original after two tries) |
| The new element looks too sharp, pasted on | It has far more fine detail than old, soft footage (about 2.3× in one test); prompt words don’t change it | Prompt words don’t change it. Keep the original for shots where it shows |
| The new creature drifts: different place, smaller, turned the other way | Reference size set to max, which lets the pictures overrule the shot’s motion | Set reference size to match |
| The background changes (different trees, sky or set) | A whole-frame redraw re-imagines it | Fine for a fast shot. For a slow one, raise the control end toward 0.75–1.0 |
| Squashed or stretched | The generation size doesn’t match the shot’s shape, or a join resized a piece to the first piece’s size | Use the file for your shot’s shape (16:9 or 4:3); finish every piece at the same size and check the first frame of each before joining |
| The color is off (too light, too warm, wrong for the design) | The look comes from the reference picture, not the prompt | Change the picture and the prompt’s color words together, then run again |
| A creature partly hidden behind trees doubles, vanishes or turns into a branch | The weak case for a whole-frame redraw | Try a new seed; if it doesn’t hold, keep the shot as the original |
| Scenery appears that the shot didn’t show (hills or trees in a sky shot) | One scene line was used for every shot | Write the scene line per shot, with only what’s in that shot |
| A second creature appears | The prompt didn’t say how many | “Exactly one {CREATURE}”; if it still appears, keep the original shot |
| The framing changed (a close-up became wide; the creature took over the foreground and the actor shrank) | The prompt didn’t describe the framing | Describe each shot’s framing in the prompt, and raise the control end to 0.8 |
| The design changes between shots | Different pictures per shot, or color coming out differently | The same pictures for every shot of a sequence |
| A jump where two parts meet | Parts made separately: the pose jumps, or the set restarts | Families 2/3: one run if it fits, or give the next piece the previous piece’s last frame. Families 1/4: cut parts at a natural pause; keep the one-frame overlap and drop the duplicate |
| Flicker on scenery or on people (the flicker check shows red blobs) | The redraw changes there from frame to frame | A new seed; for a slow shot raise the control end; keep the original if it stays |
| Something from the wrong period (modern buildings, cars) | The prompt and the still didn’t name the period | Name the period and add “no modern buildings, roads or vehicles” to the still’s and the clip’s prompt |
| Too clean or modern next to the episode | No episode frame to anchor the look, or no light described | Start from an episode frame, and describe the light in period terms. Texture words (grain, softness) don’t work. New shots can come out a little more saturated than the episode |
| A small detail came out exaggerated (a scar became two gashes) | Precise details get overdone | Describe it tightly, or leave it out |
| The camera pushes in although you asked for a still, wide shot (new footage) | The camera line wasn’t strong enough | “Static camera, no zoom, no push-in, the framing stays wide throughout”; a new seed |
| The new set is brighter than the episode (new footage) | The prompt didn’t name the episode’s light | Name it (“dim warm lamplight, deep shadows”), and use a picture of the set from the episode |
| Pale patches where the grey was (on an actor, or the set) | The grey mask in the reference was broken into small pieces, or carried on after the element had gone | Grey only clean, solid shapes; drop tiny fragments; end the mask when the element is gone |
| A beam or bolt lasts too long | The prompt didn’t say how long | Say its duration (“one short bolt”). It shortens it (9 → 6 frames in our test), but it can stay longer than the original |
| Someone in the new shot copies what a person does in your place picture (new footage) | The place picture had people in it | Use pictures of the place with no people (crop them out); say in the prompt what people do and what must not happen |
| Something switches from old to new mid-shot (an outfit, a person, a creature) | The grey-reference mask found nothing on some frames, so those frames kept the old one | Check the mask preview first: step through it; every frame must cover the whole thing. Use more words, or keep the shot original. If the mask already covers everything on every frame, see the next row |
| Part of the outfit pops between old and new where hands cross the garment (hands over the chest or mouth) | The mask breaks around the hands, whatever the words | Check those frames, and keep the original if the outfit pops |
| The shot starts in the old outfit, then changes (the old color for the first 1–2 seconds, often on a long close-up) | The mask is fine: the model starts from the old garment | More mask words or a box won’t fix it. Add a line: “From the very first frame {SUBJECT} already wears {THE NEW GARMENT}; there is never a {THE OLD GARMENT} at any moment of the shot.” A new seed alone doesn’t fix it (in our test: the old color on 57 of 218 frames, 53 with a new seed, 0 with the line). If it persists, keep the original shot |
| Garbled names or text on screen | A full redraw rewrites burned-in text (credits, captions) | Keep shots with on-screen text original, or start the segment after the credits |
| The face in a wide shot comes out soft or wrong (swap) | At full frame the face gets too few pixels | A crop route for small faces comes in a later guide; until then, keep the original shot |
| A light or color changes halfway | The prompt didn’t say it stays | Say what stays the same to the end (“the red light stays on throughout”), or change the seed |
People
| You see | Why | Fix |
|---|---|---|
| An actor became a different person | The model redrew them without enough to hold them | Name them as a subject “exactly as in the source”, and give them a face crop. In a swap, they keep their own timing and sound from the casting recipe |
| An actor vanished in one shot (a new place, with naming and face crops) | It depends on the seed | Re-run that shot with a new seed; for a medium shot, use the soft close plate and control end 0.6. Check every shot by eye, from the first frame: the flicker check doesn’t show absence |
| The actors disappear or turn into small distant figures (a new place) | At control end 0.25, a general “the people in the shot” line doesn’t hold them | Name each actor in the prompt, one line each, and give each a face crop as a picture |
| An actor is missing, often a small figure far away | The prompt said “no people”, or a whole-frame redraw dropped them | Never write “no people”. Name each person as a subject. Count the people by eye |
| An extra person appears | The model added someone to the background | Check every shot by eye. A new seed. For a new place: an empty still from a description, not an edit of your shot, and “Exactly these people appear, nobody else” in the prompt |
| A see-through double of the actor (a medium or close shot) | Seen only when the shot went in without a reference video | Use the blank-reference file: the actors stay visible in the reference, and only what you replace is greyed |
| A recast didn’t take on one shot (swap) | Where the person covers their face, the word mask jumped to another person, so their real face reached the model | Step through the mask: it must follow the right person every frame. If it jumps, cover their area with the box mask workflow (seamless-box-mask.json; still greyed in the reference only) |
| The mask jumps to someone else when your person enters or is covered (swap) | A word mask is a hint, not recognition | Use the track one person workflow from a clear frame (backward, by reversing the shot, for an entry) |
| A flat grey panel appears in the result (swap with a box mask) | The box was too big (full height, or about half the frame) | Tighten the box to the person’s shape, with a modest margin |
| A person is missing for the first second, then pops in (a new place), often a foreground person seen from behind | The model left them out at the start (the same slip as “The shot starts in the old outfit” under The picture) | Step through the opening frames of every shot, not only the middle. A “from the very first frame” line doesn’t help here: in our test it brought the old place back, or left the person tiny. Re-roll once; if they’re still missing at the start, keep the original shot. |
| A person vanishes, shrinks or is see-through in a one-person medium shot (a new place) | One-person medium shots in front of a large new background are the known limit. Part length and render size don’t change it (tested). A wide Picture 1 or a low control end makes it worse | Picture 1 = a soft close crop of what’s behind them; control end 0.6; “shallow depth of field: the people sharp and solid, the place soft”. Check each shot, re-roll once or twice, then keep the original |
| The person was seen from behind, and now faces the camera | The model turns a back to the camera | Keep the original for that shot |
| The recast person’s face differs between shots (often a box-mask shot) | Each shot is made on its own | Put the shots side by side; a new seed for the odd one out; a tighter box |
| An object appears that isn’t in the shot (a basin, a lamp) | The prompt’s scene line named it, or named something from another shot | Write the scene line per shot, with only what’s visible in it |
| An accessory appeared (a headband, a scarf) | The render added it | Leave it out of the pictures; say “no headwear”; a new seed |
| The recast person drifts back toward the original | Weak pictures | A face close-up at the shot’s head angle and a neutral expression; a new seed |
| The new hair or head shape didn’t take (short hair stayed though the pictures show a shaved head) | The grey outline keeps the old silhouette | A known limit: a very different head or hair shape may not follow the pictures |
| A grey patch on someone else (a hand, a shoulder) | A small separate piece of the mask landed on them | Remove small islands from the mask before you run |
Lips, timing and sound
| You see | Why | Fix |
|---|---|---|
| The lips don’t follow the words | The prompt has no lines or timing, or the part has no real sound | The casting recipe: the exact lines with their timing, “lips and jaw follow the original waveform”, the sound copied. Check your part has its sound. Subtitle times are not lip timing; measure the line in your shot’s sound |
| The voice drifts off the lips later in the scene | A piece’s sound is longer than its picture; the extra adds up at every join | Finish every piece with the finish workflow (exact length); for 25 fps new footage use the trimmed command |
| The lips drift on new footage in a 25 fps episode | CreateVideo was set to 25: the frames play 4 % fast against the generated sound | Leave it at 23.976 and convert the finished clip by repeating frames |
| The clip is one frame short | -shortest without padding the sound | Use the finish workflow: it pads or trims the sound to exactly the picture’s length. With ffmpeg, keep -af apad (or add -frames:v N) |
| A voice is ahead of the lips after a join | A long audio crossfade overlapped the clips | Put each clip’s sound exactly under its picture; only a short fade-out on the outgoing clip |
| A speaker’s voice changes between shots (new footage) | Each clip makes its own voice | Keep a speaker’s lines in as few shots as you can |
| The builder rejects the clip | Sound and picture differ by more than 0.1 s, or the clip is under the minimum (5 s to submit; 1.5 s for a local edit with 0.64.3) | Trim the sound to the picture. Edits from the builder need clips of 5 s or more; 1.5 s clips play only as local packs made outside the builder |
| The clip is quieter than the episode | Prime or OBS was turned down when you recorded | Record again with Prime at 100% and OBS’s Desktop Audio at 0 dB. Don’t normalize to a fixed loudness |
| Everyone looks too thin | A 4:3 picture squeezed into 16:9, or back | Crop to the right shape, never squeeze |
ComfyUI
| You see | Why | Fix |
|---|---|---|
| The run finished in seconds, or saved only a grey depth video | A picture input still has the example name, or a link in the graph is broken; either way ComfyUI skipped the generation | Load your own picture into every Load Image node; if that’s done, re-download the workflow. A real run takes minutes |
| Out of memory | The size or length is too big for 16 GB, or other apps are open | Close Chrome, OBS and games. Lower the size before shortening the shot. Check you have 32 GB RAM and a 32 GB+ pagefile |
| Results look wrong, with no error, after you download the Fun ControlNet | The 13.5 GB upstream file puts its layers in the wrong places | Use the 4.53 GB Comfy-Org copy (models) |
| The run stops with “MiniMaxH3AddGuide needs an image or an audio to anchor” | Your clip has no sound track | Add one with the silent track workflow (Capture). For a swap, use the real sound instead |
| Load Image / Load Video can’t see your file | It’s in a subfolder | Put it directly in ComfyUI/input, with a name of its own |
| Plastic, smooth skin | The older 4-step speed-up LoRA in an effects run | The Turbo v4 LoRA at 8 steps (as shipped) |