Remove air units closes with Pool form

[Courtenay]

When you are in the Remove air units step, if you open the Pools Form (Cntl-Q), and then close the Pools form, the step ends, just as if you had pushed the "end step" button or hit shift-Enter. This is very likely not what I wanted to happen when I closed the Pools form. This behavior has caused me to have to backtrack and redo things several times.