I have had this issue for 3 months, now. I've replicated over the past three patches.
Go into the HSI -> Data page -> UFC -> Press Grid
The MGRS Grid Square selection comes up on the right.
I can move the cursor around with the TDC, but when I TDC Depress (or press enter on my keyboard, mapped to the same thing,) a line flashes for .1 seconds under the selected grid, but doesn't otherwise do anything else.
I've tried repairing, etc. Nothing fixes it.
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