I seem to have the same or similar problem.
After installing Parallels Desktop 8.0.1, I proceeded to install Win 7 SP1. At the end of the installation Windows showed network type selection screen (Home/Work/Public) and was otherwise fully operational. However, "Installation of Windows 7 in progress" with the rotating wheel kept going for a long time. I rebooted Windows and Mac, and it did not change anything.
Then I finally had to choose option "Complete installation manually..." from the top Installation/Virtual Machine menu. The rotating progress wheel and "installation in progress" message were gone from the VM window, and Windows seems fully operational, but there is no Win Application folder in the Dock (despite activated option), no Parallels button in the top menu bar, no Windows volume icon on Mac desktop...
Can someone please help??