Export to Blender - "Export-Auto-UV-Decimate" ignores some Paint Layers?

[rabhhit]

Hi all, I've been encountering a recurring issue when trying to export a painted sculpt from 3DCoat.

So I sculpted my mesh in Voxel mode in the Sculpt Room, painted it in the Paint Room, then went to Export-Auto UV-Decimate as I usually do.
Usually, I don't even need to convert my object to Surface mode, or do anything else really, and the mesh and its textures will come out just fine, or may need some light tweaking but nothing major. 

Right now, it looks like during the export, most of the Paint Layers are totally ignored.

Here's how the mesh looks before export : https://drive.google.com/file/d/1Ew83fp9j5YIbFjAIf1iApoxlD2GKSmD9/view?usp=drive_link
The Layers window : https://drive.google.com/file/d/1ymdMrNlcVRhnSTOWawMWV2lrVDPUx3-n/view?usp=drive_link
The Sculpt Tree, after I switched to Surface mode to try and solve my issue : https://drive.google.com/file/d/13QEJiQojI1J_QgPMO-iE7i1DLeiDNgbt/view?usp=drive_link

Now, after the export, once imported in Blender with its textures : https://drive.google.com/file/d/1Vm5b21dQy4CdfWU2VsUEjo4Bvv-_3yOq/view?usp=drive_link
The textures exported by 3DCoat : https://drive.google.com/drive/u/0/folders/1Dpgd4v5adee-41Ie-bz9AgiNAUM0Fx1j

So as you can see, the diffuse doesn't match what's in the 3DC viewport at all, and most other maps are empty. It's like it has skipped all layers except for the one with the swirly pattern.
Apart from that, the mesh looks fine and decimated as desired, it has UVs etc.. The only problem is the textures.

Does anyone have any idea of how to fix this ? I have lost a whole workday on this already and kinda losing my mind :)))

Edited August 12 by rabhhit
formatting

[Carlosan]

Usually, I don't even need to convert my object to Surface mode

So you was painting the sculpt mesh on Voxel mode ?

[rabhhit]

1 minute ago, Carlosan said:

Usually, I don't even need to convert my object to Surface mode

So you was painting the sculpt mesh on Voxel mode ?

Yes I was, it usually isn't a problem though.
Right now I'm trying to convert the mesh back to Voxel, to see if the export would work with my usual method. But when I click "Ok" the software soon freezes

[Carlosan]

Try the same procedure on a new fresh project, the issue remains the same ?

[rabhhit]

Update on the Voxellisation test : I managed to turn it back into Voxel, did an export, still the same issue.

2 hours ago, Carlosan said:

Try the same procedure on a new fresh project, the issue remains the same ?

I tried on a new sphere, simply did 2-3 brush strokes in Sculpt and Paint, tried to export, textures are exactly as they should be : https://drive.google.com/file/d/1wuuUZPwfca1-eh0qEeOCekS2giohJk8N/view?usp=drive_link (sculpt)
the textures : https://drive.google.com/drive/u/0/folders/1iLbEHdCkYXunoyNdlmEu6AnFciy9EyP-

So the workflow is "correct" (or at least works), it must have to do with the object itself, but I have no idea what's wrong with it

[rabhhit]

Okay quick update : I tried to do a RMB on the object in the Sculpt Tree -> "Fill Voids" and "Close Invisible Hulls", then another Export-AutoUV etc.. but taking the Decimate down to ~30k polys, and it worked! I guess the topology was a bit damaged or something, since I must have stretched it while sculpting. This + the mesh being mostly hollow must have not geled well with the software.

Thank you for the help !

[Carlosan]

Glad you solved the issue