D2JSP with YAMB can do any act boss, cows, and a few other places in classic. If you are going to test this out with classic I suggest that you be very careful and make sure you don't have anything that would attempt to make you go to act5.
I'm sure you will have to do very heavy modifications to your item ini/nip files because just about everything thats configured to pick up in LOD doesn't exist in classic.