I did a few millimeters of dissolvable support, mostly for the wheels which kept coming off the bed. I like it better than a brim (easier to remove).
I couldn't fix the tolerances, but I'm printing with a 0.1 XY size compensation to tighten it up. It was pretty loose on my machine, too.
I should be able to post the remix tomorrow. I want to complete the print first to make sure it's OK so no one wastes time and money on a bad stl. :D