I have found this to be a glitch in RB and have asked repeatedly that the programmers address it, and if they did I would use RB for more than a generator and audio recorder. (For that it is great though.)

In Cakewalk, if you set up a midi vsti, close and come back later, what you pick is still there, i.e. it loads. In RB, the VST slot is now empty, if you close and come back (edit VST slot.)

UNLESSS, you choose it by way of an INSERT.

But that adds a few complications I won't go into here. It could have changed but the last time I tried, edit vsti doesn't "save" no matter what I do.

So, I just generate my tracks and go about my business.

If I used RB as my primary DAW I would be banging myself on the head though.