Whenever you want to use your formation slider, a lot of the time I need to switch it a couple of times because the formation would not change. I reproduced this now:
- select any amount of units (I also test it with 5 spearmen)
- use C or click on the formation button and directly shortclick with your rightmouse button anywhere in the field
Apparently it skips/ignores the formation but it’s still on. So when you hold down right mouse button you think it should go in formation (because it gives the lay-out of the formation you chose), while it will never do that till you switch the slider off and on (and click not that fast after that). Now I know this I know the workaround for this 
but still… for the people who don’t understand why this is happening it feels unrealiable (like me before this) and very frustrating when you see mangonels and it “doesn’t work”.
