Ok, now you've given a bit more information, I can see where it's gone wrong....you were given lots of bad advice I'm afraid.
The reason you're having problems is because you're trying to run a fully featured map on a limited RAM device, therefore it's running out of RAM & rebooting.
You need to start again & install a specially modified navcore with an inbuilt swap file which will get over the problem.
Holyhead normally deals with these but I think he's on holiday at the moment so I've modified one of his excellent posts to suit you:
holyhead wrote:Make an backup from the Device.
Delete everything on the Device
Download
[Please Register or Login to download file] & extract the archive onto the TT One
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1) Reset The Device (minimal 15 sec) and start it till the announcement "No map found"
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2) Choose United_Kingdom_and_Republic_of_Ireland 990_8306 (you've already got this map)
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3) Copy the map to your device in his own folder.
If you open the map you see the individual files and probably a folder (brand).
Not a map in a map.
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4) Download
FastActivate Extract FastActivate.exe to your TomTom device root (internal or SD Card).
Run FastActivate.exe from that location.
Select option 2 & wait for activation successful message
Done
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