@Dropky,
Thank you very much for your help.
I would like to confirm : for the BTC address, should I add ":x" behind my BTC address (like the one with Excavator 1.4.4a), or, no need to add those ":x" (just my BTC address) with v1.5.4a now ?
FYI, I did have 6 GPUs. I don't know why Awesome Miner made the config with 13 devices.

Should I edit it to only 6 devices, or, should I just leave it that way?
Please advise. Thanks.
There is no need to add :x behind your BTC address. Yes, I would advise you to edit your config file for 6 GPUs, but it should work either way, excavator is ignoring commands send for devices that do not exist.