Hello there Maxamillion, I am very experienced with using Feral Heart on a Mac and have been very successful in keeping it running smooth for years. I am a little rusty about this because i haven't been on in a while, but i'll try my best to remember what I used to do.
Your problems could be either of these:
Option 1- VERY IMPORTANT FOR ALL MAC USERS!
DO NOT place your Feral Heart folder or icon on your desktop or doc. Not sure why your mac will not allow you to play if it is visible, but you can't. Instead, create a folder on your desktop and place all feral heart related things in there as well as the main folder with the icon (actual game).
Option 2- WINE
You may need to install WINE (if you have not done so already). It should tell you that yours need to download it when you install FH, but if it does not you could google it.
Option 3- too many downloads
You may have downloaded too many FH's. Press the search bar and search "feral Heart" and move everything (except for any maps, presets, etc.. that you would like to keep) to the trash. Also you may need to delete WINE and re-intall. Then re-download FH and WINE.
Option 4- Your computer is blocking it
Go to your system preferences, security and privacy, general, at the bottom there should be options that say: "allow apps downloaded from:
- Mac App store
- Mac App store and identified
- Anywhere"
Make sure "anywhere" is pressed so your mac knows that you can use FH.
Hope these help. Little rusty so I'm not sure if this is everything, but it should help.
- Shay