This system is designed to work with all types of games but is built mostly with Survival and RPG games in mind. Equipping equipment (especially weapons and tools) using the hotbar is common in survival games. If you are making an RPG game you might want to disable this feature and add the main hand slot to the equipment window instead.

You can disable this functionality by setting the AllowEquipFromHotbar? boolean to false in the Equipment Configuration section on the AC_InventorySystem you attached to your player controller. By default this option is enabled.

If you want to equip the main hand through the equipment window you would then add that specialty slot to the profile used by the player. The Equipment Slots page goes over equipment profiles if you need help with them.

Equipping equipment through the hotbar is designed to override anything equipped in that slot in the equipment window. It is also used to equip items that don’t have slots inside the equipment window.

For example in the demo you can only equip weapons through the hotbar and everything else is equipped through the equipment window. You can however override what is equipped in the equipment window through the hotbar. Let’s say you have the yellow smiley face helmet equipped in the equipment window, and you have the red angry face helmet on your hotbar. If you select the hotbar slot holding the red angry face helmet it will equip it, overriding the yellow smiley face helmet equipped through the equipment window.