What version of OS are you modding?
What Nav comupter are you using (Mk3 or MK4)?

If you are using a Mk3 then it's a very tricky process indeed, even for changing something as simple as changing the splash screen, every file that gets modded must have the same format as the orginal, also the saved ISO file (ready for burning) must be of the same format as an unmodded iso,

Also x8 may be a bit on the quick side, I always burn a OS disc at x1 speed.

I have a pile of coasters so high Sir Edmund Hillary would have a job climbing it.

HTH.

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Sept 03, M3, Silver Grey. Retro-fits: Modded Mk4 DVD Drive, OEM Bluetooth, VR Control, Rainbow Speaker Upgrade, Sony SOT Amp, HK Sub, CCFL, Intravee II, NightMode.