I can't offer you too much information on training resources, however, anecdotally I can say:
Sys admin training. This is quite simple and those people I have explained the system too have picked it up quite easily. I think the only real difficulty is ensuring you highlight and explain some of the overly techie ACS stuff... for example in group admin, most users I come across immediately ask..'Whats a composition mean?'
I also think end users are equally as easy to train, but with specific reference to the CMS I think this interface is a bit clumsy and pretty difficult to communicate. Again, slightly too techy would be my observation, however, I expect in your circumstance they are only likely to need the basic of some derived/cut down version
I guess what you're asking is 'Is the OpenACS a low cost, low maintenace way to acheive your goals.'
Yes, absolutely! Training is pretty easy, and once you've got a server up and running, from an admin point of view, you can largely forget about it.. leaving you lots of spare time to figure out why the J2EE, Tomcat wonder beast on your other server is still down and showing no signs of re-surfacing...
