.fbx greater than 50mb

I found the answer to my own question. Bottom line.. you should never be importing anything even close to that amount of memory. Sumerian really isn't designed to be used in that way.

https://www.youtube.com/watch?v=gy7Z5aoixbY&t=1506s

Yeah, I was going to suggest splitting that FBX up into smaller chunks. This will make your workflow a lot faster, too.