To those reading this with the same issues, I finally got the 1.8 driver working by following the instructions on this
knowledge base article and fixing the
file permissions using the Disk Utility. Afterwards the driver works fine, Finder opens, flash works, login screen displays correctly. No probs what so ever so far.
To Displaylink, your customer service sucks. Either your forum support are not even aware what's on your site or you have clamped up to remove yourself from any liability of screwing up so many peoples system. Not the way a successful company operates either way. You could have at least posted a link to the fix.