My save from 24.01 started working again after installing radioactive 25, is there any way to make the saves functional at non modded versions?
I gave this some more thought. Ultimately, RenPy is a really odd bird. I think what is happening is that it is trying to side-load Radioactive's data without being asked to. The problem here is that I have created a new object (RaPerson) that it doesn't understand, and thus doesn't know how to side-load.
You can take it back to the base game without full mod releases with a minor amount of effort. Grab
game\radioactive\RaPerson.rpy from Radioactive and throw it into SuperPowered's game folder somewhere. I did some basic testing, and was able to load up a save using this. Doesn't require anything else from Radioactive or GetLucky. (It looks like it might even still preserve the data, so you could go back to Radioactive later if you want to. But I wouldn't bet the farm on that.)
Unfortunately, while it is possible to delete the objects and even the object definition, it looks like it isn't possible to remove all trace of an object due to RenPy's rollback feature. So you will probably never be able to play that specific save completely unmodded again.