Runes of Magic US / AU

If your topic is still current, in the EU Forum the Repairme-Developer has
announced an update (actually changed beta version 0.7 from 3rd June to release)

Link to EU-Forum: Click me

Link to CurseForge: Click me

That won't change anything about the OP's problem.

The reason why you have to use this slash command instead of getting your equip automatically repaired is simple: Gameplay relevant stuff has to be initiated by a player's keystroke or mouse click. To implement time delays in addons, developers do NOT have any wait-like function you would have in a macro. Because of that developers basically use something, just that I do not want to go too deep into details, called "OnUpdate" which is triggerd every new frame drawn on your screen to get the elapsed time and basically create timers with that. But once you are using OnUpdate you will loose the keystroke or mouse click context and thus are not able to execute some stuff. As far as I know using items like potions and repair hammers is, just like casting spells, blocked from being used in a OnUpdate.

Ohhh, sorry. I apparently didn't read that properly.