To load on a mac, assuming you've download and decompressed the file into your download folder :It can't be opened in Mac, I've been trying to open the app with the terminal and with a patch and still doesn't work. If someone achieve to play the game in Mac I'd appreciate if can tell me how.
Open terminal and type the following :
chmod -R a+x /Users/(your username goes here!)/Downloads/LongStoryShort_v0.8.2a0.3-mac/lss.app
Then exit terminal, open system preferences security and permit the lss.app to load, at this point the game should load.