I've been trying to use Dynamic thermo, but the problem is that the objects in the level get destroyed, how do I stop this from happening? And also how do I lower the thermo when using the dynamic thermo.

I would try using a permanency tweaker tool on the objects that disappear. that should fix it.

And for the last question, The dynamic thermo loads areas of your level as your player is near them. So basically, things only load when they are in view. That mean, that the dynamic thermo is only useful in a spread out area.

I hope that all made sense.