Ya... MapTools lets you set up your own grid... Most VTT's do so I would advise against it, good choice with that.

Great looking map, the only improvement (probably for later maps since this one is in the complete stage) is that caves rarely have such smooth and curved walls, granted there are plenty of them out there, the feeling I get when I see it is something that should look a bit rougher and less circular. Other than that... great job, can't wait to see some more!