The problem installing GPE Timesheet has gone away. If anyone else is having problems please report them here.

The import problem is (in my view) a bug in the Maemo Calendar program export code. I will add a workround in the next release of GPE to ignore the bad alarm repeat interval but, in the meantime, if you get that error when importing a file from Maemo Calendar you can work round it by making changes to the file. Use the following command line to fix the file:

where file1.ics is the bad file from Maemo Calendar and file2.ics is a new file which will be created with the problem corrected.