@rainycrystal Your best bet then is to have the different skills set hidden in a key item. Nobody said the recipe books had to be actual books. Have a common event parallel process that checks your skill level and reward new recipes to the player as they gain skill by sneakily adding recipes to...
Check two things. One did you give the book to the player? They must have the book on them. Two, make sure that the plugin command is calling the right crafting window. If neither of those two things work then triple check your spelling.
I'm using your Map Item Drop plugin. Works beautiful, but I do have a slight issue. For some reason for each map item drop I pick up, I get 12 items worth. I don't really want my trees, mushroom, or anything else for that matter dropping 12 units each time.
Might start playing some rpg maker games and uploading the games on youtube. Realistically they're not going to be for views. Just to give anyone some feedback on any games they're working on. So if you'd like me to play and review your game just reply them down here. And I'll upload them on Rpg4MGames.