Thanks ! found it: something wrong is inside \Documents\3DCoat2026\UserPrefs A new folder created by 3DC at start solved the issue. (time to find the reason)

It is working well from my side! 

fresh install paint.mp4 //edit It was fixed after deleting \\Documents\3DCoat2026\UserPrefs

Version 2026.19 - seems like Smart Materials, Presets, Alphas, etc. are fine after update, but almost all the folders with custom shaders are empty. These few custom shaders that are left are messed up, doesn't display properly.

Can you explain how to replicate this?

PPP result: anyone ?

Fixed on version 2025.19

Windows, 2026-19 3DCoat-2026-19.exe 3DCoatTextura-2026-19.exe 3DCoatPrint-2026-19.exe - Fixed an issue with GLTF scene export when visible objects mode was disabled.- Fixed "Specular Color only" and "Metalness only" view modes. - Write "[floating, used X of Y]" to persistent log file "Documents\3DCoat202x\FloatingLicense.log" with ISO UTC timestamps - Approximately 150 automated crash reports processed; a large number of crashes fixed. - Fixed severe UI lag that occurred when tweaking node properties with sliders in Per-Pixel Painting mode. - Fixed an issue where the final merged texture of paint layers would show an opaque white background in erased areas instead of being fully transparent.

I updated 2025 to 2026, and it feels unusable compared to the 2025 version. When I load a painted model the texture loads piece by piece and the viewport feels sluggish and choppy. Does anyone else have this problem and is there anything that I can do about it? I have to use the 2025 version as it works smooth as butter.

Here https://d345hrihx5j0zk.cloudfront.net/3DCoatTextura-2025-17.exe

Change the method from line to object Hope this help

LOL that goes back to 2011. Heres the manual. 3Dcoat-manual.pdf

Could you share the download link for this version? 3dcoat texture 2025.17

Zooming with Alt+RMB work as expected The viewport refresh rate only affect Mouse Wheel zoom

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