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Firstly, NEWER research Tasoth Commander.

Then, you need to remember to have some stuff stored before researching the tech prior to this item.
You need a MC-Reader before researching MC-Lab, or else no MC-Disruptor
You need SUB Construction before researching Transmission resolver.
You need a Deep One Terrorist before you Research Ion Beam Accelerator.

Remember to research a Lobster Man Navigator before you research Magnetic Navigation.

Then there is a string of tech to keep in order to obtain all the armors.
Deep one corpse --> Aqua plastic --> Plastic aqua armor --> Ion beam accelerator (Remember to have a Deep one terrorist alive before researching Ion Beam Accelerator) --> Levende deep one terrorist --> Ion armor --> Lobsterman navigator --> Magnetic navigation --> Magnetic Ion armor.

That should cover the bugs. Enjoy
TFTD earned its own page for this material on the OpenXCom wiki: describes the various dead ends in more detail.
While this information is readily available on several locations online, this brief overview is very useful indeed.
Post edited January 21, 2019 by sykopat
I'm fairly certain the version GOG was provided is not affected by this bug; to the further point, OpenXcom indeed doesn't have this dead end.