Okay I have got Microstudio to work in Win2000 again. You may not believe it but it was the NEW aspi drivers keeping my drive from being recognized. Nero worked because the WNASPI32.DLL version it uses is ver 2.0.1.28. So I copied the nero version of the dll and replaced the WNASPI32.DLL in \WINNT\system32. I can copy discs but I cannot play any with these drivers. Maybe I need some version between 2.0.1.28 and the new 4.6.x for the play function to work.
The new ASPI drivers do NOT work with Microstudio v2.3.0.3 and Win2000.
While i was trying to get everything to work again, I set up my machine to dual boot to win98/win2000, to see if I could get it to work. I installed Microstudio in win98 and it saw the drive. I then installed the new aspi drivers in Win98 and the drive was gone. That's how I discovered the problem.
So the bottom line is I have microstudio v 2.3.0.3 installed in W2K and can copy discs, but cannot play them. Maybe if I had the new Microstudio and the new drivers everything would work fine.
It's too bad MTU doesn't offer a free upgrade for people like me.