For tutorial sakes, ill use ??? as my ID map.
Go here C:\BF2_ModTools\data_???
Double click on it and wait for menu to come.
Choose mapname and you will see description and name
Cho0se name and look for your map ID
Once found, select it and simply go to the box the red arrow is pointing at and rename your map.
Once done go to File/ Save
Now just sit back and relax till the saving is complete. Usally about 1 to 2 mins.