[Keith_]

So I've done some experimenting. I've tryed it on several games using different races. Here are my findings:

1) Go to the Army setup screen in a province that contains multiple units of the same type.
2) Either Double-click on a unit to select all of that type in the row or Shift-click on a two units to select all the units in between.
3) Clicking once more on either the unit which was double-clicked or the first unit of the Shift-click will cause the game to crash.
4) Clicking on any other unit in the selected group simply removes that unit from the selected group as normal.

Keith