Complex question:Calligrapher, File Explorer, Storage, BIS, and CF

[basil]

I've installed Calligrapher on my x50v and so far it seems quite good. Still in the trial stage. A few questions:

1) I first installed it to BIS and it didn't quite work right. Also, after installing it, a new BIS item appeared in my File Explorer. So, now there is BIS and BIS 2. BIS 2 has all of my stuff, but BIS has "Inbox.mst 29698 etc, etc," (Etc = more numbers, obviously). What does all this mean? Can I delete this BIS that has only the "inbox.mst" file?

2) In my BIS2, there are a few more "inbox.mst###" files. When I click on this file, by the way, a subfolder called "mail attachments" appears. But it's empty. Can i delete these "inbox.mst" files?

3) I reinstalled Calligrapher with the default installer, to Main memory. The BIS and BIS 2, and the "inbox.mst"'s are still there. No biggie, except I don't like looking at them.

4) Here is the BIG QUESTIION: Can I move Calligrapher from Main Memory to either BIS or my CF card?

Sorry for the long, interrelated questions.