Hi sebastian ! 🙂 Sorry, i have no experience with powerblock but do you have read other recalbox project in the forum ? They have some Nes WIP like the WIP of @Grumlyzhttp://blog.recalbox.com/forums/topic/projet-recalnes/ with led indicator. May be that can help you :s. (It's in french but doesn't Hesitate to ask help :s). Happy to see you in The recalbox community :).