I've never seen that. I wouldn't think that was a VPN issue. Does it look like it might be a graphics issue? You might try disabling accelerated graphics (from the menu select "Help" ---> "Settings and Performance"
Hi Barbara. I use 8.1 thru VPN on an almost daily basis without any problems. I would agree with Joshua that I would not think it has to do with VPN.
I had similar issue when i first installed 8.1 desktop client. It has nothing to do with the VPN. I did the same thing what Joshua mentioned. Disable the Accelerated Graphics option from Help --> Settings and Performance menu. It should resolve your issue as well.