Pete - forgot to say - the zmaps need to be rendered into a non-lossy format like png or bmp otherwise the z-ordering won't work as desired. The lightmap and main scene render can be any format (jpg,png,bmp).
Leto - thanks for the suggestions, I've actually got a bunch of 'floor tiles' in cardboard format from various board games I've played over the years which have a lot of those sorts of things. Very useful suggestions though. Because it is kind of an endless dungeon hack like the Roguelike games I am trying to steer clear of making the rooms too 'specific' in function - especially as the rooms are moved through in a semi-random order.
Leto - thanks for the suggestions, I've actually got a bunch of 'floor tiles' in cardboard format from various board games I've played over the years which have a lot of those sorts of things. Very useful suggestions though. Because it is kind of an endless dungeon hack like the Roguelike games I am trying to steer clear of making the rooms too 'specific' in function - especially as the rooms are moved through in a semi-random order.