Im guessing its your inverted day/night temp causing the problem as well.
Not sure if i caught everything but are you burning ng or lp? Lp definitely needs dumped/exhausted. If you have an exhaust set up, you can set it on a rh controller to dump moist air so the dehuey doesnt make it too hot in the room lights out. Or set the exhuast on a temp controler for when the dehuey makes the room too hot. Are you aiming for those low daytime temps?
Burning LP. I do have it exhaust some during lights on. The only time I have a hard time keeping temps where they should be and the right day and night temps, is when it's like -20f - -30f. Other than that I can keep things pretty steady. We pretty much just got done with having over a month of below zero weather all the time. So I just put things back to the way they were before that cold spell. Also cut the lights down to 10 on, 14 off, which I think I already said, lol. I ripped right now.