It is a "limitation". 😢 The idea is that the character isn't suppose to be able to carry anything (beyond blueprints/planners) but when you "reset" an assembler's recipe, the items inside the assembler go to the players inventory. I've tried to design this mod around the APIs permissions system instead of the events (during the second revamp). The early versions of the mod were event based, but that led to lots of bugs including ones that could cause the destruction of the entire contents of containers -- very bad.
I'm not happy with the current state but I'm also not sure how to get the desired effect (a player without a "real" inventory) without lots of bad bugs. This started as one of my first mods so it also has a lot of legacy code. I probably just need to redesign it from the ground up, maybe with some type of mix of events and permissions (and prototyping). But I'm also not sure when I'll have the time to do a big revamp either. 😓