ISTR I needed a Java runtime bundle to use PalmThing (memory is working very slowly this week--sorry), which I downloaded here (http://www.palm.com/us/support/jvm/download.html) and which does have Mac installation instructions.... Hope that'll help.

I'm guessing that the interim file exported from LT would work for your mother, at least, since it can be opened in any spreadsheet program.

Good luck! :)