Actually... it IS the lockout that's causing your problem. The lockout feature has become an open circuit. It supplies the ground circuit to every switch besides the master switch, so when it goes bad, no other window works. There are instances where repeatedly hitting the lock switch while holding one of the other window switches will cause the circuit to wake up.
You have everything needed at the master switch to operate all of your windows from there, so your power and ground feeds are OK. It's an internal switching problem within the master switch that's giving you trouble.
Write back if you have any questions.