That mechanic is meant to enforce building a real building for your machines not just a plate or block above every machine and everything is fine.
So the rainexplosions will stay as it is. The only problem i have with them so far is, that the new oil drill and miner that has to be build away from base is a bit annoying because of that.
I'm fine with it being a mechanic, but it should probably state/document somewhere that this is a mechanic. This is my second InfiTech2 server. I'm starting to get to the point in the game where mk1 fusion isn't really that far off, and I JUST found out, through swift and immediate removal of my entire quarry and support structure in a way that only GregoriousT can accomplish, that rain hitting the side of a machine and blowing it up is a thing.
And it appears I was just bitten by this again today when I logged on this morning:
Yeah, the side of the top floor of my factory was open still, but there were no machines that didn't have at least a 1 block overhang. AND there were no machines that hadn't been sitting there for over 2 weeks. I closed up shop last night and went to bed. Log on this morning and I have this... I wasn't even online to see the goddamn explosion.