Ok - I got it :P
1) You need Windows (Tested with Windows XP)
2) You need this
3) Lock your device and hold RESET (bring it to recovery mode)
4) Unpack the Archos firmware
5) open cmd and locate the afptool.exe (copy update.img into same directory)
6) run "afptool -unpack update.img unpacked" without quotes. This creates a driectory "unpacked" with the file contents inside.
7) plug the tablet in (it should be install drivers)
8 ) start RKAndroidTool
9) clear everything and select each image and set the offsets (HWDEF file!) (dont worry, I've forgot the offsets, so an error occurs.)
10) Click "EraseIDB" and then "Run".
12) Unlock the tablet and start it
13) have fun :P
14) Oh, maybe you want to format the internal memory to Fat32, if so, simply connect it via USB and format it using windows.