Lower- I read in your post,"while other paint is still wet". Createx offers a free product info & technical guide booklet for their Auto Air line of paint. Time and time again they emphsize "work in light coats, very light coats". I had never before used waterborn paints and found them to handle quite differently than anything else. For me, anyway, the booklet was a must read.
Createx, 800-509-6563,
www.autoaircolors.com (sorry, I'm a computer moron,dont know how to post a link)