Well, I found some stuff, but so far nothing that would quite explain the bug in question. However, I was able to resolve some other bugs. One allowed you to unload a gun more than once, if the second or third backpack containers were open. That should no longer happen. Also, there was a strange situation where the weapon in your first equipped slot would not be clickable if you had your second or third backpack container opened. It was only clickable when the first backpack container was opened.

So here you can see the laser pistol is selected, while the second backpack container is open. You can also see that I was able to successfully unload the weapon.
Oh! I also highlighted the little square that tells you which backpack is currently open (currently opened containers are shown in orange). Note: If you have not upgraded your backpack, you will not see those little square selection buttons. However, once you do, it will be easier to know where you are looking in both your backpack, and your ship's storage.
I am still going to be trying to recreate the disabled inventory slot issue, and hopefully find a solution for that. If you have any insight as to the cause, or are able to recreate it, please let me know.
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