Good Luck With This One. Lol

I drive a 1996 Mercury Sable GS

When the car is in Park everything operates fine.

When the car is placed into gear the power steering does not work, the power windows do not work, the radio does not work but the lights all work.

I talked to various mechanics but they seem to be at a loss. If it was an electrical short is it possible to have all these selective electrical issues and yet still have all the lights(turn signals, headlights, interior light, etc) operate normally? And as mentioned above, everything operates correctly when the car is in park?

Have you seen this before because everywhere I go it seems to be something noone has ever seen or heard of before. I have googled the issue all the way through the late hours and have found no solutions.

Your invaluable expertise would be greatly appreciated.