Do I have to revert back to android first? What do you mean 115K4? s805-autoscript?
Not sure what you have on the box but you need to go to his forum and read a bit. Yes to boot his rom you will need to install that rom over the original rom. Format the SD card, extract the 115k4 rom to the sd card and toothpick boot. Hold the toothpick in until you see the Android Robot and the rom starting to install. The posts I mentioned tell you how to do the rest.