I recently purchased the md-11 when I fly with 100 % fuel according to the FSX on screen report, I get a message that fuel is criticaly low in the selected tank. I can't figure out how you can tell which tank is selected. I can get to the screen that shows the tanks and how much fuel is in each one, but can't determine which one is selected. Can someone please help!

Are you using the PMDG load tool to select how much fuel / passengers / cargo you want?

The way that PMDG designed the fuel system is different than the fuel system used by FSX. FSX tanks are side by side with a pipe connecting them. Unless the MD-11 herself is reporting low fuel don't worry about it.

Yeah, turn off the flying tips. FSX doesn't know how to interpret what the MD-11 is doing.