I wouldn't trade in your WarpEngine for a 3640. You get much more and faster memory. I would upgrade it to a 40MHz 68040 though. You could try Piru's exec.library replacement and see if it works. You would need to use LoadModule instead of the AmigaOS 3.9 ROM update thing. You can split the "ROM Update" with Piru's Blizkick utility and LoadModule those updates (with fixes) too.