Cypherc: I answered that back on the Nitdroid/Multiboot thread.
Page one has what's working and what isn't. Otherwise, it's just an Android build - Go Nuts with it.

As for this market fix:

I can not test this fix as I am at work and no access to WiFi for NITDroid.
This most likely will not work, as it tries to match the build version to another file, but if we can "spoof" it to thinking it's a HTC Desire/Nexus One, that could also work.

If anyone would like to try be a guinea pig and test this fix:

Then, once it reboots, go into the dialer, and type

*#*#2432546#*#*

A message should pop up into the status bar after a few seconds depending on your connection speed saying checkin succeeded.

Now you’re good to go, open Market and download away

Terminal Shell Method:

Get the Froyo.zip file from XDA developers forum and copy on root of your sdcard, then open terminal shell on our phone.
reboot

Upon booting back up, open Dialer and type in the following code

*#*#2432546#*#*

Once you see a notification in the notification bar that says checkin succeeded you can now open Market and are done.

I do not think it will work as it's not an official build or device, but if we mix a file from a legit device running Froyo, it COULD work.
If someone can send me build.prop & froyo.prop from a legit device with Froyo, I will see how it goes.