James

Hey guys, I have a mid 2012 MacBook Air I'm working on with some strange behaviour I'm trying to diagnose. There is no SSD...

You should be using something that's plastic safe. What I use and CRC in particular recommends is QD Electronic Cleaner for computers and other sensitive electronic parts as it's less harsh. Contact Cleaner 2000 is for use with things like circuit breakers and other simple metal electrical parts, and according to its data sheet it's not safe for use on plastics which is why it damaged the housing.