I have been able to get Windows 7 with Stellarium and the USB cable to work. I had problems with the USB driver up until I found this site.
http://www.totalcardiagnostics.com/support/Knowledgebase/Article/View/92/20/prolific-usb-to-serial-fix-official-solution-to-code-10-error
I have been able to get SkySafari 5 Pro on iOS to connect to the the SkyFi emulated port on an Android connected via USB.
I have not been able to get SkySafari 5 Plus on Android to connect either on the same device or a different device. It keeps defaulting back to the demo interface.
The virtuoso app works perfectly fine.
You only need pro for telescope control right? If so it looks like the SkySafari 5 Android and iOS code handle Sky Connections differently, possible even just doing a simple port 80 check.