When I rotate the assembly it leaves a grey trail and the whole screen eventually turns grey. I have tried saving in different views and reopening but the problem continues. Any suggestions?
Why am I getting weird graphics issues?
You will need to provide more info - graphics card, driver for Graphics Card, filesize of assy or part, processor speed, RAM on board, etc.
Try also turning off all view settings such as real view, perspective, Shaded edges... and see if those change the behavior
Retrieving data ...