When placing a upgrade module such as the efficiency regulator while building a room it's not removed from your inventory, lets you place as many of them as you want once you've gotten just one
CS EDIT: LINK to the thread with additional information about the bug.
Huh, additional information, it appears to be either level dependent or sandbox dependent, will do some additional testing, when I attempted it to get you the files and video on chapter 8 everything worked as expected, but when I returned to chapter 1 it failed to deduct properly
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Hey Balenar! I am sorry to hear you are having problems with your upgrade modules!
Our team will definitely would like to take a look at it but to do so, I have to ask you for some game files so please visit this LINK for instructions on how to get them.
If you would also be able to record a short video showing us the problem, that would be lovely!
Best,
Dominik
Hey Balenar! Thank you for providing additional information about the bug. I will be forwarding it to our developers for investigation.
I will bring you any updates as soon as I hear from them back. I appreciate your patience!
Best,
Dominik