I seam to have found a bug, the source file is "B1 B2", but I have been unable to reproduce the bug in a new file.
I created a map with the shaded hexes in place.
I palced units.
I deleted the shaded hexes.
I could them move all but one unit.
The "Flesh Ripper Brute" on the top Left could no longer be selected.
I saved the map, Closed the Editor, reopend and selected edit.
The Unit is now selectable again.
Hope that helps.