Walkthroughs for custom maps.

Hello! I played it the other day, but on version 1.6.1. On 1.5.4, the window opens, but I can't enable the "invite hero" function for some reason.

This doesn't depend on the version of the game; it's the same for both SOD and HotA. You need to enable this option in the settings (see the screenshot):
UI.Tavern.InviteHero> = 0
You need to change 0 to 1.