Hello,
You can use Away Builder to prepare the model and textures.
First, import your model and textures into Away Builder.
Prepare your model with different textures for each part.
Then, export your model as AWD and use it in Cyberix3D.
wiki.gamemaker3d.com/tools:away_builder
Another way is to use the SubModel command block.
If you have two sub-models, for example, throw two SubModel blocks inside your model.
Then set the first SubModel's model number to 0 and set the 2nd Submodel's model number to 1.
Then set a different texture for each SubModel.
Regards,
Cybeirx3D team