Neil,
PrPro can have some issues with certain VST's. Some can load fine, but not work in PrPro. Some, however, will fail upon launch, not load, and will be written to a "blacklist," in about PrPro CS 3 and later. After all such VST's have been added to the blacklist," PrPro no longer tries to load them, and launch proceeds smoothly.
However, that does not seem to be the issue with iLOK, as you are not getting the hang of PrPro during launch, and it seems that iLOK is getting to the point of loading, except for that license data. This is just a thought, as I do not have, or know iLOK, but perhaps some aspect of its loading by PrPro is failing to find that license info (ini, or similar file?), so its loading is not completing. Do you know where that licensing info is being stored? In the loading process in PrPro, are you presented with an active dialog screen, that might allow you to type in that licensing info? It might take a contact with iLOK's T/S group, to find a way for PrPro to get past that point, and act as a proper host app.
Wish that I had more, but can only rely on some general experience with PrPro hosting of VST's.
Good luck,
Hunt
