So... aside from the "where to put files in this new cryptic repository" problem, I've found another.
When I try to save a new dashboard (see, bi-server 5.0 ce is running nicely, and showing CDE alright), I get a huge error.
When I try to save a new dashboard (see, bi-server 5.0 ce is running nicely, and showing CDE alright), I get a huge error.