All my sculpting was baked before the conversion to CC3 base plus even though the converter does it as well.

The toes and nails sculpted the same way are completely fine. I've tested the conversion to the 4k preset and normal and there is no difference.

In the image below I've sent both the original and the converted base plus model to Zbrush for comparison. The dark brown is the original and the peach color is the converted version.

The base plus forces the thumb position back to a more human structure -spread out rather than keeping the morphed shape.
The finger nail sculpts seem to be stretched and the position and angle are extremely out out place. The texture stretching can be seen in the attached image.

Please let me know you've investigated this. I'm trying to get this bear to the Marketplace asap.