To answer your question above: Don't feel the need lose the authenticity just to make things easy to understand for US/UK readers. Almost everything seems to end up altered to cater to us, and it really shouldn't be.
If you need to, put an asterisk by a word/phrase and explain it at the end of the chapter, but don't change how you write your story just to suit your audience it terms of losing the authenticity of the Irish experience in the process. If I'm going to read a story from someone from another country, I want to see their experience, not the one that's been watered down for the English. < 3