Just managed to compile the RK27 SDK fully.
Copied it over to my player, this one:
And guess what it worked! I can play music and navigate with the buttons and the FM radio works too!
Just one snag however, the display was white, but I have got a fully working firmware (apart from the display).
I have just started looking at the screen drivers to see about giving them a tweak like I did for the RK2606 firmware.
This firmware seem quite up to date, just looked at the source and it features album art and nes emulation.
If I get further success I will post some photos.