for the record, I just discovered that while you can save a worksheet with a name like
you cannot open it (with Maple 15, June 2011)
Maple will return an error message like "file mapleprimes.mw could not be found" (swallowing up the "mywork," part of the name)
but if you rename it mywork-mapleprimes.mw
it will work fine.
In other words, do not insert commas in file names.
I do not know/remember if...