reasons why your map couldnt work:
1.-you used a wrong unit id
2- the .unl file has a wrong name. correct naming example :BrisbaneCX.img + BrisbaneCX.unl (same name,different extension)
3- wrong path- Correct path example :sd/Map/BrisbaneCX.img + BrisbaneCX.unl
4- wrong map : in 37xx series and newer just FID 800 tweaked maps work
5- wrong FID generated .unl - correct FID is 800
6- wrong tweaked file : download from pop222's CXs with FID 800 for 37xx series original post on Noeman.

PS: in other CX compatible models, you can use also normal locked maps ,but you have to add an .unl file
made with the map right FID and PID 2, as explained in my thread linked above-