Has there been any movement on this issue? I am currently reproducing this problem on a Win7 x86 VPC running CCS 5.5.0.00077. The host is a Lenovo T530 running Win7 x64 Enterprise. The VPC has been assigned 2GB of memory, though this appears to be a problem with CPU usage only.
My symptoms are very similar, except that since I'm in a VM the process will only ever consume 1 core (VPC can/will only assign 1 core per VM). This behavior is triggered consistently by entering a debug session and isn't fixed until I exit CCS and re-open the workspace. It's making work very, very painful.