The rocket will erroneously refuse to launch:
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Here is the save file in which it occurred, at the time of those images. Some minor visual mods are used but nothing that changes any behaviors.
https://cdn.discordapp.com/attachments/ ... a63deb08b&
Note that this issue will not occur if the number of newly used slots is zero, ie if every item stacks with an existing one, the launch will succeed. To test that in the above save, just grab 25 efficiency module 2s from the chest slightly to the northwest (next to the EM plant making them) and replace the 5 tesla turrets with them in the rocket.