Last day I lost power to the heat/AC control system, cruise control and windows.

The items that have stopped working on your 1999 Oldsmobile Cutlass share the same electrical feed from the ignition switch. With the help of a wiring diagram this circuit should to be checked to see of power is being supplied to by the ignition switch.

i am experiancing the same problem with my wifes car it just started, i have done everything you have, checked all fuses replaced a hvac relay. did u get your issue resolved and if so how did you? or what did you do, any feed back would be great, we really dont wanna have to put it in the shop right now. thanks much.