asys3,

my youngest keeps picking up my tablet and reading through the graffiti wall and finding things which interest him and drawing more and more.
He had me drawing James (from thomas the tank engine) the other night and was great to have him explaining what he needed to make it look right

As for export formats, theres nothing explicitely built into the system yet, I have been having a bit of a mental block regarding exporting bitmap images to PNG.

However I have done some initial testing with SVG, the results are quite good so far.

http://liqbase.net/liqriver.php