The Windows Phone 7 platform has been slowly and, for the most port, silently gaining momentum since the release of the first Windows phone. With Windows 8 right around the corner, one can only assume that development for these devices will continue to grow as more devices become available and MetroUI becomes even more widely appreciated. For those carrying the Nokia Lumia 710 and 800, the development has been pushing along just fine without Windows 8.
XDA Senior Member biktor_gj has recently released a ROM that is supported by the Lumia 710 and 800 that is the first of its kind to support NAND Access and InteropUnlock which is a huge push forward for ROM development.
For those who don’t know what InteropUnlock is, it is best explained by the Windows Phone Hacker Wiki:
Interop unlock is a term that refers to the ability to deploy applications using the interop capability on devices updated on Mango or above. Prior to Mango, applications using interop drivers, such as registry editors, could be deployed if the device was unlocked. In the Mango update, however, Microsoft chose to block the capability, preventing the deployment of these applications.
The installation process is pretty complicated and, until someone can port the process to Windows, requires users to be in Linux. Users are also having problems with making sure they have unlocked bootloaders first, as many who do have them are getting incorrect information when plugging them into their Windows PCs. It does take some diligence, and will likely frustrate some, but the end result is well worth the hassle.
For additional information, download links, full instructions, and troubleshooting posts, hit up the original thread.