3D Model for Hololens 2 (CLOSED) (CLOSED)

Hi Guys. Pleased to meet you. I'm a noob at 3D modelling and am looking to create and manipulate models for Microsoft Hololens 2. I'm looking for some advice. I have created a very simple box in SketchUp and applied 6 pictures (Jpegs) to it. I've exported the model as an .FBX file but it just comes out as grey on the HL2 3D viewer. I've also tried exporting as an .stl but have the same problem. Can anyone help? Thanks.

Sounds like an interesting project! I hope you can find someone to assist. 
I have moved your thread to Technical Talk.  
https://www.renderhub.com/forum/technical-talk  

Ah right. Thanks very much. It seems I've done my usual and just blasted in rather than looking for the right category!