I have yet to try it, and have searched for an answer but cannot find one.
If I start a project in AXP on a Windows based system with all media stored on an external drive, can I connect the drive to a Mac and continue the project? Will there be any problems?
The problem that you'll run into is hard drive format. Mac can read NTFS formats from Windows, but cannot write to them. The best thing to do is to have two copies of the media, one on a Mac formated drive, one on a Windows formatted drive, then just copy the Avid Project files back and forth as necessary.
For what it's worth I do that all the time and have never had a problem.
You could format the drive to FAT32, which both Win and Mac can use. But even then, especially if you use P2 cards, having your media on 2 different drives makes you sleep better at night!
fat32 should be fine. I have been using it extensively with FCP and havent run into many problems. Just make sure Avid has a setting that lets you limit your files size.
It looks like avid has 2 settings, "Capture to a single file, 2GB limit" and "Capture to multiple files" and it lets you set a max. capture time. Either setting would work fine as long as you keep the capture time down to a reasonable size.
Either way I dont think its going to effect how long of a clip you can import within Avid itself, this just effects the file structure.