One of the reasons it doesn't "work" in FS2002 is that, as I understand it, some of the gauges are actually modelled as parts, using xml animations rather than made as "gauges". Since FS2002 doesn't recognize XML animations, the model is not "backward compatible"
wow that sucks....is the PMDG 737 as good as the 747?
spare yourself the anger and go out and pick up fs2004. you can probably find a regular copy of it for $20.00 at an Eb or something.
I've had every FS since the beginning and the freeware add-ons you can add to FS2004 make it worth upgrading from 2002. Then you can go about pruchasing your payware (ppssssst- go for the pmdg 744)