bp eating inconsistently

[Bogertophis]

Don't offer any food for a while- not until she's been consistently warmed up to the right temperatures (as given above) for at least 2 weeks. Any sooner is likely to fail anyway. When it's time to offer food again, offer what she has been consistently eating previously- it's not a good time to take a chance that she'll refuse to eat- and if she does refuse, you won't know for sure if it's because the FOOD is different, or because she's still not comfortable, or because she may even be ill. So try not to confuse things with different prey.

Your second heat lamp for the "cool side" should AT LEAST be regulated by a lamp dimmer (aka rheostat)- easily available from most any hardware store & not expensive. Thermostats are better but cost more- however, safety should be your primary concern- a snake that gets too hot can be injured or killed, & since they're stuck in captivity, it's only fair to put their safety & welfare first.

Insulating a glass tank is easy & you can use many things, from sheets of styro-foam, cork tiles or sheet cork, or thick (corrugated) cardboard, or foam-centered poster boards (these are the easiest to cut neatly), or even the "bubble-wrap" some use to insulate hot water heaters. Cover the back & sides, & underneath except where the UTH is- that MUST breathe a little for safety so it doesn't over-heat & short out.

If you don't want to see the "insulation", install scenery first, then the insulation behind it.

Most ppl seem to find that the damp towels on top don't add effectively to the humidity- & remember that heat rises, so most of that moisture is going into YOUR room, not the snake's.

What works instead is to reduce the air-flow that's carrying away the moisture in the air- you want to cover most of the top with something that air cannot pass thru- again, many things can be used, from foil to glass or to plastic- anything air doesn't flow thru. Obviously you need to leave safe spaces around the overhead warming-bulb fixtures, but with minimal air flow, the humidity you provide inside the tank will mostly remain there.

The reason that PVC enclosures "retain humidity better" is because the ventilation is very minimal- so that's what you want to duplicate here- it's no real mystery. Neither glass nor plastic allows humidity to "escape"- it's all about the openings, & glass tanks usually have a whole top that's open-air, compared to a few tiny holes & minute gaps around the door of a PVC enclosure.
See?