How low is the humidity?
Are you adjusting the temps in the cage via thermostat since your room temps fluctuate so much?
I'd be more worried about low temps and high humidity than ok humidity and perfect temps. Just me.
In the winter, my BCI and BP tanks are around 55-60% on average and I mist with warm water every other day. So, they average about 60%+ - higher when in shed of course.
In the summer no problem keeping it 60-70%.
The problem with good humidity but low temps is you can have shedding issues anyway, and get an RI or other illnesses because it is damp and too cold.
Same with humidity that it too high - regarding illness like RI.
Again, there has to be sustained imbalances with animals like BCI's, BP's, etc. Other species of Boa's, for example Rainbow Boa's, true red tails (BCC), etc. are not as forgiving.
So, if you are just working on dialing things in now, don't freak out. It will probably be fine.
Good you are paying attention and want what's best for your BCI.