The two versions of VE are the pro version and the non-pro version. The non-pro version is the old Vienna Ensemble. It only exists if you need it for compatibility with old projects,
The Invalid project occurs if the conversion to iLok fails. The conversion seems to be unreliable for large projects. I have noticed two scenarios that work reliably for me.
One: if you still have e-licenser control center installed, you need to do the "offline conversion method". Just plug in your e-licenser key to do the conversion.
Two: if you uninstall the e-licenser control center software, then the "online conversion method" works reliably.
You can monitor the conversion by showing the Vienna Helper app (it's in the right side menu bar). It shows up if a conversion is needed. The Vienna Helper app should show only "converted" or "cache hit" entries. If you see errors or broken pipe messages, then your conversion failed and you'll eventually get an invalid project message.