Why isn't it mo chuid airgid?
Should it be incorrect to not have the space after the m' ? As with English, I though abbreviations like this are treated like one word, but this is marked as "almost correct" rather than "correct"
It is incorrect. However, there is a bug in Duolingo's system where you can't have the space, so unfortunately it can't be written as m'airgead
Too many double negatives here for me to follow. Space is correct or stuck together is correct?
I don't see no double negatives, but to answer your question, space is incorrect; it's just a bug in Duolingo's system.