Yes, running XPmode is running a virtual machine.
Most likely nothing is wrong with the install. You might not have the system resources available or allotted to the virtual machine. Remember your running two operating systems, plus any background programs each OS is running, and AutoCAD. Ideally you'll want a dual or quad core CPU and at least 6GB of RAM with Windows 7 64bit (So you can use that much RAM). Then devote 3 or 4GB to the virtual machine.