I suspect Entourage got the regular Android SDK, with a modified emulator together with some own "libs" that makes interaction between the e-ink and the LCD possible.
We only need those libs, some "hello world" examples and specific eDGe function breakdowns to get started. this together with some instructions (if the eDGe got some unique preferences) to get the ball rolling.
(well, I need an eDGe too, but i haven't been able to get one yet, as I don't live in the US)

But it can also be that Entourage is holding back the SDK until they release the next firmware version, like lifting the eDGe platform to Android 2.1?
Who knows?