Overheating in Vacuum? [SOLVED]

Greetings everyone

For a while I've been having a weird issue.

You see, I play JNO using a custom Real Solar System planets pack, the one by user Avinashkma, although modified by me to have realistic settings and a custom launch site because the original one has a very unrealistic atmosphere for earth.

Update - 10/11/2024:
I fixed it, ignore the post lol.

I also play with a bunch of mods, mostly to add parts and extra features.

I have an issue which is that for some reason my crafts begin overheating like crazy when they reach vacuum, like, it only happens when exposed to sunlight. They rapidly overheat for seeemingly no reason and take damage until they explode and that has made it impossible to play the game.

For over a year, hell, perhaps even two years by now I've been tweaking around the planet settings, the mods that are active and so on yet I can't get it fixed consistently. I have to reset and make a clean reinstall every time for it to get fixed and sometimes even on the default system it happens.

If anyone has had any experiences like these, I would gladly ask for your help to try figure out what's going on. If needed, I'll add my current modlist as a comment.

Thanks in advance.