Did you install the 4920 dashboard from slayers? If so then the kernel wont let u run the 4920 dashboard hence the error 16. You need to find a copy of the latest dashboard to restore your box, and then softmod with uxe.
I have cured this problem , heres how i did it.Bought a crystal 1.6 from game, took it home, used 007 to ftp in and copy the c drive to my pc, took it back to the shop and said didnt want it, (Thanks game, love your money back gaurantee), wrote a dvd with the dashboard files on it. Then put the twoboxes back to back with the hard drives removed from the cases but still plugged in, u can slightly loosen the ide cables to enable a faster easier hotswap. Power up the modded box and go into boxplorer, put the dashboard dvd in the modded box, select drive d.
POwer up the 1.6 box, as soon as u hear the drive spin up (just as the animination starts to fade) pull out the ide cable from it and hotswap the hard drives.
It has to be then because otherwise the kernel detects the dashboard is incorrect and locks the drive quick, i think, any way later than this and the hard drive is locked again.
Now select drive c in boxplorer and u r in the 1.6 hard drive, wipe it and copy over the dashboard files from the dvd to the now blank c drive, when done power down both boxes and put em back together , enjoy.