Thanks Keet,
It's true that the cylinder method is simpler but the room method is valid for any shape the room has.......just draw the walls in the appropriate shape and you get the model with which to drill a STRAIGHT wall.... ... and can be resolved with an export/import even if only temporary (for the single purpose).......
This will be my last message on this post....I will open a new one if necessary.
Greetings and thanks again