<r>Thank you guys <E>:)</E><br/>
<br/>
I created the room with walls first and despite trying to be very carefull, as I ran into trouble with double walls before, somehow I messed it up.<br/>
<br/>
I just re-created the room from scratch, this time room first, walls later, then adding the slopes and ...

Hi,

I uploaded an example: http://ul.to/u6attfyz

The ceiling should be visible in bright purple but instead one can see the sky. What am I doing wrong?

Regards
Simon