R3D engine, Revolution3D is a known illegal engine based off of the TV3D engine (TrueVision3D). When TrueVision was open source, some kid took the sourcen and "created" his own engine out of it, titled it Revolution3D. This was a very very long time ago, since then both engines have supposily recoded their engines to be quite different "under the hood".
So if your using it, you should know of its illegal background
Anyways... to answer the question...
Since R3D_Engine is an activex class, in order to use that in VB, you MAY be lucky enough to use a proggie caled Activex2DLL, look in the Announcement forums. The only very very bad thing about using the above, is that it is SLOW since it uses scripting....
Until then, Ive heard rumors about PB's ability to use ActiveX, but so far NOBODY on the forums have been able to give a real fully working example. Last I heard it takes as many lines of code to craete an interface and functions to use an activex controls, as it does to create Windows XP....
Good luck.