This tutorial probably applies to very few people but whatever.
Step 1:
Download winebottler from here https://winebottler.kronenberg.org/downloads
Step 2:
Open it up and install just the "Wine" application.
Step 3:
Now you can double click any executable you find on the internet and run it on OS X.
Notes:
This is fairly buggy with gm8(.1) games so be aware of that. Not all fangames work. I've had experience with them randomly crashing or crashing after a couple of seconds. I'm pretty sure gm:s games work good for the most part.
Make sure to reply if you experience any issues, I will try to help.
Ciao
Oh boy, do I have an interesting story to tell;
On my first attempt in downloading wine from that link, I accidentally dowloaded shitty mac adware in the process. Chrome was all messed up, I couldn't click links, even Safari was broken. I was fucked. Then I found the adware I was looking for...and also a keylogger that had been on my computer...for over two months. The bright side was that I got all of that removed and I couldn't be happier about it.
I downloaded Wine and WineBottler, but was having cabinet issues that prevented me from opening the game up, but I eventually got it to work! (Holy shit!)
***Here is a detailed step by step album of how I got IWRTM to work on my mac using Wine after following the above steps:
https://imgur.com/a/oUZG2Thanks again for your help MrSlick and patrickgh3 !!!