If you have a Tomtom with the bootloader version number starting with 1.xxx instead of 5.xxx you have a special system and should never attempt to change your bootloader! (exception: bootloader 1.0012 is OK for updating.)

It is most likely that you have a special Navcore version as well - 8.041
Other Navcores won't work on your device the progress bar will stop at the end end the devices freezes.
The only way to use non genuine maps on these devices is by using a specially patched PNDNavigator for the 8.041 Navcore.
Don't try to patch the ttsystem or the PNDNavigator file yourselft it won't work and the ttsystem does not need any patching.

Only the new PDA maps will work as you need at least Navcore 8.2xx for the full featured maps.

Link for the pre-patched [Please Register or Login to download file]

The bootloaders 1.0100 and 1.0200 are designed for devices with a "bug" in the filesystem or the GPS hardware.
Tomtom has provided this "quick" fix to be able to sell these units (most of them being ONE V8 models) without sending them back to the headquarter in Holland.
If you bought one of these units and you are still in your warranty period ,try to get a replacement unit with a normal bootloader/Navcore as it is most likely that Tomtom won't offer any updates for those devices!

Thanks to Downunder35m