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When completing the mission UNC: Besieged Base in the Chohe system of the Hades Gamma cluster, if you have Unlimited Medigel activated from the trainer your game will hang forcing a hard reboot(unless you are playing in window mode and can get to your taskmanager to kill the process).

At the end of this mission you are awarded Medigel as part of the mission reward. I suspect because the trainer probably prevents the value of medigel you have from being modified this reward causes the game to hang because the quanity can't be updated.