Order of classes affecting functioning of app.

I don’t have the slightest idea about why my program doesn’t work when I move my main class to the front instead of 3 places down where it normally was, but is the order of the classes along the top bar supposed to affect the app? And does anyone have any suggestions on moving classes around without affecting the app?

Im guessing you are using global variables?

if you do

tab1:      a = class()
tab2:      b = class(a)

then tab1 must remain before tab2 for b to be defined correctly

If more than one tab has a setup or main etc function then the one furthest to the right is run(I think)