It should all be fine for the most part and all assets I have tried simply by copying them across work without issue.
So far anyway
However my Custom Scripts that Amen created for me no longer work in Max.
( But they are Unique and written for purpose )
All the Stock scripts for Classic still seem to work fine.
Not quite sure how the old AI will work yet but personally i would rip all that out before import and use Max's
The only person ever to get all his work done by "Friday" was Robinson Crusoe..