Hiya Truepunk and welcome.

distance from lights: between 2'-3' from light source, depending on position in tub.

temps: i don't measure them, but it's below freezing outside so there is a constant flow of cold air coming in. i'm guessing anywhere between 55-65 degrees fehrenheit. very cool nevertheless, and always cooler than room temp. no discomfort at all when placing my hand at the top of the canopy, plants are too far from the light for that.

air circulation: i forgot to mention that the in line vortex fan is acting just as an exhaust, sucking out all the heat from the bulb, and that the air intake of the closet is passive. both use 6" ducting.

That's a serious fan for 64 s/f. I'm curious, do you use a fan speed controller? What's the noise level? Are you cooling your light with it, just venting the room, or both?
while the flowering space is only 64 sqf the closet is larger. it's divided into 3 sections, one for a mother, one for clones and vegging, and one for flowering. unfortunately, the flowering space is far too small and the other two sections far too big. in any event the fan exhausts air from all three sections at once, which is 192 sqf, a size more suitable for a fan that powerful