I've tried to create custom formations, or just use the already set ones, but none of them work for me.  No matter what I do my party moves in a wide oval formation when ordered to move together.

I don't think a wide oval is a default formation. Maybe it worked after all, the first time. It would be helpful to change the look of the formation icons to look like the actual formation. If they could just move the dots around on the icon we wouldn't need to memorize which number goes with which formation.

I don't think a wide oval is a default formation. Maybe it worked after all, the first time. It would be helpful to change the look of the formation icons to look like the actual formation. If they could just move the dots around on the icon we wouldn't need to memorize which number goes with which formation.

No for me, no matter which formation I choose, no matter how I customize a formation, the party always moves in a wide oval formation, every time no matter what formation set is chosen.

I have the same issue.

From what i've found the characters have a certain area of exclusion around each of them so they have a certain spacing between them which will change the formation and is very dependent on the facing direction.

 

If you have the whole party selected and use right-click to move and orientate them you should still see the formation in yellow and this should allow the formation to be kept more readily as they tend to move out of formation when the "front" isn't entirely specified. Also I've found when you set up the formation, diagonally the portraits can touch, but vertically and horizontally if you leave one grid square in between each portrait it gives the party more room to form up correctly.

 

Hope this helps, you might have already figured this out.