OK, the actual use of BAT is for bulk changes, if you just want to change one gateway, why don't you simply go to the CUCM config and change it????
If you still want to export the GW config to change just one, you'll need to use the export option, and export all the GWs, delete all the ones you don't need, and change one gateway you want to change.
As for phones, there are already export options for phones that you can use search criteria in BAT and get just the phones you need/want.
HTH
java
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