Hi Avi,
you may want to look at an old, often forgotten, concept in SAP Personnel Development: the development plan. Sounds to me like this is exactly, what you want:
you can define plans including various training types and once an employee has done them all, there is a porcess to transfer skills from teh plan (as opposed to just from the individual trainings) to those, who complete the whole plan.
You could even add other things than training types. If you require someone to have worked in a certain role (SAP: job) for some time to gain practical experience before they get a certificate, that's also possible.
You find dev plans in the menu here:
It's a bit too much to explain the whole thing here, but as far as you don't find it intuitive and the field help and help in the IMG are not sifficient, SAP online doco will probably be fine. It's also described in the SAP PRESS book about "Personnel Planning and Devenopment".
kind regards
Sven
