OK so it does take "some" runway data base info but...
How come if you program runway 24L and at the last minute they change you to runway 24R more than 1/2 mile away you don't get a warning?
First I think it depends on what version of EGPWS is installed. Our CRJ's level D simulators had Mark V's, so I would assume this aircraft does too.
Second, there are a bunch of different software versions/mod status for the installation, and no real requirement (in the US) that I know of to keep the fleet at the same status. You would assume everyone does, but...
Third, was the terrain database current?
The Install manual does say it receives "Selected Runway Heading" from a ARINC 710 (FMS) source.
From what FE Hoppy was saying, and the Mark V pilot guide:
The Terrain Clearance Floor (TCF) function (enabled with TAD) enhances the basic GPWS Modes by alerting the pilot of descent below a defined “Terrain Clearance Floor” regardless of the aircraft configuration. The TCF alert is a function of the aircraft’s Radio Altitude and distance (calculated from latitude/longitude position) relative to the center of the nearest runway in the database (all runways greater than 3500 feet in length). The TCF envelope is defined for all runways as illustrated below and extends to infinity, or until it meets the envelope of another runway. The envelope bias factor is typically 1/2 to 2 nm and varies as a function of position accuracy.
That is one very very smart box.