For folks who are having problems keeping groups grouped nicely in battles, here's a couple of tips:

1) One or twice I've had the strangest bug where, no matter what I did, particular units or groups insisted that they were selected, no matter how much I selected other ones - even if I ungrouped and regrouped the group that insisted it was selected, or the other group that I actually wanted to be selecting/moving.

It was solved by selecting All groups (Control-A), grouping everybody together with G into one big group (which abolished all previous groupings), and then ungrouping everybody (G again). THEN making the groups you had before. Now everybody will work as expected.

This workaround solves the very annoying "stuck-on-you" bug.

2) Another consistent bug - or just functionality, whatever - is how a given group will often insist on keeping its current "formation" which is actually a snapshot of some previous moment when they are haphazardly placed relative to each other. Orda and others have complained that they have to place each individual member again, etc. (and of course, this is often only a rough approximation of what you wanted).

The easy solution for this is to select the group in question, then give it a formation command, such as Single Line (Shift-1). Use F1 to see all the formation commands. Issuing a formation command immediately turns a group back into an "easy elastic band", like they were in MTW. Whether you can actually want one of these new formations is up to you - but Shift-1 easily solves all my problems with "will you morons just line up!"

A couple of other things that might trip newbies up, but aren't bugs:

1) If you select a group, you will not see special function buttons light up unless EVERYBODY in the group is able to do it. For example if you have a bunch of Principe units but ONE of them has used all their spears, the "fire at will" button will be grayed out and it's status can't be seen or changed (unlike in MTW). The solution is to individually select units that (still) have the ability in order to see and/or change its status.

2) If you use Pause a lot, you'll notice that e.g. the Run button will be incorrect, if you wanted to e.g. issue a new move command, then hit Run, to make then Run there. (This is if it took careful placement and you weren't able to just double-click.) You have to take Pause off for just an instant, for their Run button to light up (i.e., for them to accept the run command).

Likewise if you wanted to move your whole army up in formation, you will not see the placeholders for anybody if you do it while in Pause - which makes it hard to keep them near each other. So move, say, the frontline troops first, un-Pause then Pause again, now you'll see their placeholders, and can place others near them.