Hi Tom,
I haven't seen any UML that covers everything. I use eclipse and emacs. Using eclipse you can open any class and see all the methods, hierarchy, etc. You can browse around the classes. Its like Javadoc on steriods. You can also refocus on a class.
The data model of CCM is similar to OpenACS 4.5 but there are already differences. If you are already familiar with ACS 4 tcl or OpenACS 4 data model, you should be at home with CCM. But there is no direct SQL manupulation on CCM like OpenACS. All custom SQL are in PDL and basic select, insert, delete, update are done on the fly.
