It's a rare error, but one other Mac user has reported this. Running this command fixed it for them:
chmod +x Secret\ Little\ Haven.app/Contents/MacOS/Secret\ Little\ Haven
I'm actually trying to figure out a fix for this - it's an issue if the game manages to detect very rapid double-clicks and confuses them for the click-and-drag behavior, and since the listened click-release has already happened, it never lets go. I'll hopefully fix it really soon!
Click inside the Reminders window, then click the File button on the top bar, and then click the New button in that drop-down menu. As soon as you make the reminder, the dialogue should advance. :)
Congratulations on the success of ONHS! It's nice to see other peoples' visual novels about trans women too, especially visual novels that are topping the charts here on Itch! I wish you the best of luck, and I can't wait to finish your game! ^_^