Hello,
I followed the YouTube tutorial above and was able to successfully complete the workflow using a Character Creator character.
I am now trying to apply the same workflow to a custom character that I created myself, but I am encountering an issue.
After creating my custom character and following the tutorial step by step in Unreal Engine, the character correctly switches to the talking body animation whenever I interact with it. However, the lip-sync does not work at all. The mouth does not open or move in any way while the character is speaking.
For reference, I have already tested all available lip-sync modes/settings in Unreal Engine, but the issue remains the same.
I have attached screenshots and information for almost every setting and asset that I thought might be related to the issue, including:
If there is any additional information, file, or screenshot that would help diagnose the problem, please let me know and I will provide it.
Thank you for your help.
Best regards,
I forgot to include the YouTube tutorial link in my previous email.
Here it is: https://youtu.be/nyPNP-S92QI?si=-py_vMBtowfxVuUZ
I’m trying to understand how the character lip sync system works.
It doesn’t seem like the mouth movement is driven only by blend shapes.
I added weights to the jaw root bone, and as expected, it seems that not only the blend shapes but also the jaw root (jaw bone movement) is affecting the lip sync.
However, when I look at the Character Creator characters used in the tutorial with Convai, it seems like the blend shapes are contributing much more significantly to the facial animation.
I’d really like to get my character’s blend shapes working in the same way.
I feel like there must be a way to make it work, but I haven’t been able to figure it out yet. I’ve been researching and trying different solutions with ChatGPT and Claude, but so far I haven’t had any success.
Could you please point me in the right direction or let me know if there’s something important I might be missing?
Please help… 
Hi dada_jo, with Reallusion we recommend using the CC5 HD facial profile, and after exporting to unreal make sure that the blendshapes appearing are Metahuman blendshapes, the ones with ctrl_, and that you select Metahuman Blendshapes as the Lip Sync mode.
And yes the jaw bone and most of the facial bones of the face contribute to the animation, even the material parameters for wrinkes on the character, so it is very important to ensure it is CC5 HD for maximum quality.
Hi, I have a follow-up question about using a custom character with Convai.
I built my character completely from scratch in Cinema 4D (not based on a CC5 base mesh). It has a full custom topology with 52 ARKit blendshapes already created.
You mentioned using the CC5 HD Facial Profile — but does that mean I need to rebuild my character using a CC5 base mesh from scratch? Or is there a way to apply the CC5 HD Facial Profile to a fully custom character that was made outside of Character Creator?
If CC5 HD is strictly required, what would be the minimum workflow to get my custom character working with Convai at an acceptable quality level?
I see, then it should work with ARKit blendshapes lipsync mode, let us check the compatability of the current Reallusion Animation Blueprint with ARKit blendshapes and will get back to you, it is probably thinking that your chaacter is a CC5 based and therefore not working well with ARKit.
Thank you so much for checking. If there’s anything I can test on my end, please let me know. I’ll keep exploring possible solutions while waiting for your response. Thank you again!
I also found something important to share:
I tested the same mesh in two different ways:
- C4D → UE5 direct import: ARKit blendshapes are visible and working correctly
- C4D → CC5 → UE5 (via Auto Setup): ARKit blendshapes disappear completely
It seems like CC5 is overwriting or removing my ARKit blendshapes during its Auto Setup process, possibly replacing them with its own facial system.
Hi everyone,
I wanted to share the solutions I found for integrating a fully custom character (built from scratch in Cinema 4D) into Character Creator 5 and Unreal Engine 5 with Convai AI dialogue. Hope this helps someone in a similar situation!
01. Importing Custom Blendshapes into CC5
Used the OBJ + ObjKey workflow via the Expression Slider Editor.
- Export the base mesh as OBJ from CC5 (File → Export → OBJ → Keep Facial Expressions in Nude Bind-Pose) — this generates both the .obj and .ObjKey files
- Open the OBJ in your 3D tool (Zbrush in my case) and sculpt the expression
- Import the modified OBJ back into CC5 via Facial Profile Editor → Edit Expressions → select the target slider → set Target Morph to File → load the modified OBJ + ObjKey
- Repeat for all 91 expression slots
02. Fixing Arm/Leg Mesh Penetration in UE5
Some CC5 animations were designed for standard CC proportions, causing clipping with my custom character’s body shape.
- Opened the problematic animation in UE5 Level Sequence
- Converted the Animation Sequence to Control Rig
- Manually adjusted the affected poses
- Baked back to Animation Sequence
03. Fixing Character Position Sliding Between Idle and Talk Animations
The character was sliding left/right when transitioning between Idle and Talk animations due to Root Motion.
- Opened the Idle animation asset in UE5
- In Asset Details, enabled Force Root Lock
- Problem resolved immediately
Hope this helps!
