I was entering leaders for the Chinese NRA in Vassal. So whatever reason I decided the check the values I had on my list, which is a text copy of the ILS leaders. While I was comparing that to the counterset, I noticed the order in which they are presented was completely from the order in the counterset. I don't see why the order in the ILS would matter. Nor does the order have any relevance to my purpose. I was just wondering if the ILS keeps the leaders in the same order in which they were entered or does it sort them in some way?
Having entered a lot of leaders in the ILS, I can tell you that it sorts them alphabetically by nation, then service, then rank. The sorting occurs each time you hit the 'save' button on the 'Edit these leaders' page. I haven't really kept note of whether it sorts each rank by morale and/or modifiers, but my impression is that it does.
As you pointed out, the sorting doesn't really matter to the function of choosing leaders.
I know it sorts alphabetically by nation, then rank name, then (apparently) numerically by value. I was just curious.
In the Vassal extensions, I give a letter ID for each leader. That's for those scenarios that have you select a leader over randomly drawing one. Captain A always had a lower front side value than Captain B.