As reported by some people on a server I was able to recreate this problem by building a ship with the multool. Starting up in weld mode the tools will not pull components from adjacent inventories but would still build blocks up to 100% without using components at all. While in grind mode once the tools inventory filled up there would be no more components added to the ship nor show up in space like they would from vanilla grinders. I deleted the settings file and reloaded the game with no change in outcome from the same tests. With the vanilla settings file I spawned an asteroid and mined it until the tools filled up again the expected behavior is that they unload themselves but would not.

Here's the contents of the debug file:
https://pastebin.com/jN4P0ntp

I can provide a censored version of the spaceengineers log if you think it would contain relevant info.