Ok, I checked like a gazillion of these forum posts and even called tech support and got nowhere on this. the plugin dll fix did nothing for me. but guess what! I typed this issue into Youtube of all places and got the REAL fix for this issue and it works on studio 8 and Pro 8.

One simple change is needed as follows (windows Vista 32)

Control Panel>System>Advanced System Settings>Advanced> Performance Settings>Data Execution Prevention (DEP)>Turn On DEP for all Programs EXCEPT>add the directory to Vegas.exe