You can order a " singe group attack" when you have several units on the same hex, so you order the attack to several units at once. Is not gonna be different if you order the attack to each unit one at a time, is just something that would save you some mouse clicks, is the same as "group move" vs "single unit move" for moving units.
Yes, this I understand, but I'm trying to figure out why in this case the game does not allow me to order group attack even though there are two units in the same hex.
Can you just dump the .SAL file, zipped of course, here? I'll have a look.
Here you go, hex 5,37.