I've never used corn flour...can't even think if I have seen it here. I use quite a few different GF flours...millet, chickpea, rice, coconut (Yum!!), potato (and there are tons more) Would they work for thickening like corn? Not sure on that one.
I've found most of these flours work nicely if I make a blend of them, and esp. the coconut as it just won't work on it's own, but adds a yummy taste to things like pancakes!