Hi Juanjo,
I'm currently re-evaluating OpenACS. Without an ERD it would be hard to do. I can't believe things have change that much since the days of Arsdigita. Whether the schema has 200 or 500 tables it doesn't really matter. The value of a toolkit like OpenACS lies in its data model. There must be an ERD somewhere.
Thanks Juanjo.
Don, are you around?