rocknrollstar : If you're using 2003 server, the following hotfix may resolve the problem support.microsoft.com/kb/925336 (or you can install the MSIs individually, as you did)
chrbb : The entire collection is about 3GB in size and includes all 28 of the 2Simple programs, so its quite a hefty package - apologies if its taken up so much of your time. I think contink has a point, and I will recommend the help notes are updated so that we suggest using the individual MSIs via GPO as an alternative.
One other installation option you might want to consider is to install "Collection 1 Lite" instead of "Collection 1 Full" on each machine (ie excluding videos) and instead make the videos available on a single shared network drive. Most of the videos are also available online at www.2simple.com/videos. This saves about 850MB. Additionally, some of the more bulky installs in "Collection 2" which are flash-based could be installed centrally (such as Stories 2 Tell, Talking Stories, 2Simulate, Simple City, Maths City) - and the remaining ones could be allocated individually via GPO.
Incidentally, did Purgos give a specific error message when you tried to use the MSIs with it ?