Carceri is a seperate project. More about it will be announced this year. As for now, I can tell, that it will allow the user to create a simple coffee-break roguelike with NO programming experience. People willing to take the time to learn a few things about Lua will be able to create something more complex (although still limited by the Engine limitations). I may prepare a Doom-themed modul some day ;-).
As far as Carceri and DiabloRL they will get their own Forums once I make proper webpages for them ^_^.