What should happen is that when you select a staged mission and then load it when you go to populate mission, your name and the names of all the flights should be listed. It doesn't seem to matter what side you are flying, both Knight and Bish flights are listed for you to choose from.
The first one I uploaded, when I went to load it and run it in a custom arena I got a blank populate screen.
Ranger checked it out and said the countries didn't match and once he rotated countries so the bish and knight bases in game were the same as in the mission, it worked.
Since then I have checked it out and now it doesn't seem to matter what order the countries are in, when you select the mission the countries automatically seem to rotate and you get a populate screen listing your name and the available flights for both countries.
I then uploaded the same mission (renamed) after making a few changes and even when I was sure the bases were right I got a blank populate screen.
Ranger hasn't as yet had a chance to check out my latest problem to see if the problem is on me, but since others are experiencing the same thing I suspect there is a bug.