Squad Settings Issue Thread - Vector Thrust

I've followed TS' instruction to create a squad

-Go to the squad tab,
-create a team
-set the index number the same as the player team (default 1)
-create a squad and give it a name
-Go to the player window and set the squad, if the squad is not there, change the player’s team to the same index number. Add it as leader (you can add everyone as leaded, but only will be valid the last unit to be added)
-add a few units to the squad and then test. If everything has been done correctly you should see the squad commands in the command window.

However, even if I created a squad & team first (team ID is correct), I'm still unable to assign player's squad as the combo box is greyed out.

Moreover as I've mentioned in the comment, once I ran a test run, all squad configurations were mysteriously deleted once I return to the editor screen.