I encountered the same problems being EasyStudio 2.0 (release 01/04/2005) crashing (c++ runtime error) when I tried to sync with Outlook Calendar (contacts and tasks went fine from the beginning).
I found out that there where 2 COM ports enabled in settings -> phone monitor settings -> tab com ports. After I disabled the port that I don't use with my bluetooth connection, the problem was gone and the sync suit did it's job (even with recurring appointments).
I sometimes get a synchronization error. I fix it (but it is a workaround!!!) using the Easy Studio file and pim manager. I delete all the phone appointments and perform a full sync using the PC Sync application afterwards.
