I'm updating my dad's nuvi 2515 to the latest uk maps.
I only have experience updating my tomtom.

I've downloaded the "UK & RoI: Image UnLocked" file from this page new-maps-f88/city-navigator-europe-ntu-2017-t18606.html

Is that the correct file and what other files will I need to download?

I also have this page ready for when I do the update tutorials-f90/step-step-replacing-internal-map-nuvi-1xxx-2xxx-and-t9026.html

Cheers

Hi! You need also all the rest of the files your device support a lot of features so download also the other files and put them in the same directories like the previous one which you take backup before! First try with the .img file to see if it is supported your device may need to be patched in order to recognize open maps!

Thanks.
I deleted the gmapprom.img and gmapprom.sum and copied in the downloaded gmapprom.img.
I then replaced the largest db in the SQlite folder with the downoladed file D3413200A db.

BTW. The link in this forum for that file shows as "File has been removed due to copyright issues".
On this page : new-maps-f88/city-navigator-europe-ntu-2017-t18606.html

The "UK & RoI: Image UnLocked" file I downloaded has three different JCV folders
JCV_LaneAssistPortraitFull
JCV_Nuvi-40,50-Android
JCV_Split-Screen

but the garmin only has one JCV folder just called "JCV".
I copied in the jcv file from the laneassist folder because it had a similar file name.

Is that the correct file to replace and if so how can I test if it works?
The map seems to work fine and it has my sisters street on it which is a new street.

Correct! It seems that is working!

OK Thanks.
I've updated the maps, junction views and speed cameras and it all seems to be fine.
When I connect to Garmin express it shows as a map update available but it shows as the older 2012 map.
How do I disable or work round this?

I used garmin express to update the software version before uodating the maps, is it better to avoid garmin express and just update here?

Yes you don't need express but even if you use it you may update only firmware or other utilities not maps