@heresy
This reply is not timely sorry, i only just now noticed and read your post. If you still need help to solve you may need to give some more info after trying again as below.

Some thoughts:
Firstly, 1xxx devices don't use NTU (Unicode) maps, they are only offered NT maps by GarminExpress.

Secondly, QuickCure3 usually works with 1xxx devices but not always depending on the problem causing the soft-bricking.

I get error message "The GARMIN device is unable to program the requested memory region.
This could be due to an incompatibility between this application and the GARMIN device.
If this error continues to occur, please contact GARMIN Technical Support."
That error message may be only due to the device and Updater.exe losing communication, for instance by the device dropping preboot mode, or due to some corruption in the cure RGN file, but it can also be indicative of a damaged flash region that cannot be written to. I suggest you re-make the cure firmware and try again to flash but this time ensure that the RGN is loaded to Updater.exe with it's GUI visible on your desktop and the radio button next to "USB Device" selected. Ensure your device is fully OFF, not just in standby. Hold the top LH corner of the nuvi's screen and connect the device to the PC watching the window next to "USB Device" for it's details to appear. IMMEDIATELY you see the window populated, press OK on the GUI and keep holding the screen firmly.