Before converting your routines I'd recommend printing out a copy of your Blitz BASIC program so you have a reference as you convert them.
[offtopic]
You people are such treekillers, wasting paper like that. Whats the difficulty in using ALT-Tab. You can paste it all in notepad or open another instance of the IDE even, or if you have tabs in the IDE just keep swapping them! I really cant understand (especially older people) who print absolutely everything they can only to throw away the paper 10 seconds later!!!
[/offtopic]
I believe it wouldnt be too hard to retype much of the code and convert other parts manually, but first you must have basic knowledge of max.