Your issue looks like the recent bug described here coming from a regression in AMD driver. Install driver version 22.5.1 to go back to a working solution or run the program in 32 bit with DirectX if you don’t need too much memory (see FAQ).
If you have the time, it would be nice to report this issue to AMD so they can fix it.
Thank you very much for your prompt help. I'll have a look at that.
I love this software, I build all sorts on it, a 60,000 seater stadium (Celtic Park) I'm now working on a large theater that once stood in Glasgow, The Apollo, holding over 4,000 people.