Thanks for the compliment :)

as far as the pressure sensitivity goes, thats my problem! I dont know if I can get the plug-in for the mac. So I have just been using the airbrush, the hard edges make the lines way worse I think. Any suggestions on getting pressure sensitivity to work would be much appreciated~!

Nice watercolory look. :)
As far as I know, there is no plug-in for mac...

You've probably already tried this but the pen tool on low opacity might help for fine lines. I don't use Lascaux so not sure about it in that applet.

If you use chipipaint you can use the smooth tool and it helps make lines smoother and gives you more control and check the jtablet download for the mac online, I think you will also need java