Hoffmeyer's Giganotosaurus & Substance Painter?

Rezca

I have Substance Painter 2021 and wanted to give making some textures for their Giganoto a try, sine it's been so much fun doing so with the T-Rex 3.0  HOWEVER  the model's got around twenty unique textures for it,  five alone on various segments of the tail(!!?),  and as a result the model's just shy of impossible to paint in Substance since its treating every one of the twenty three selections as its own unique material with no ability to cross over them.  Painter keeps talking about how simple and easy it is to load a model with multiple materials and then paint across them, but I'm not seeing anything of the sort?

 

I've tried every format and export option available and there's really no change.  What am I doing wrong?  Or is there a way to get the model into a way that Painter can recognize the tiles properly?  The software I'm using mainly is Cinema 4D R23 / S26,  but I also have zBrush, 3DCoat, Blender, and Painter 2020.