Go to the first menu of the BC Manager View / Midi / Input Messages (general) press Record on the new window and check in the Byte column that you are getting the correct messages.
Perhaps post them here.
If you are getting what you want and its not changing the Korg it is likely you sysex line is incorrect.
I couldn't find the Arp sysex definition on the web - perhaps you could point me in the right direction.
All the best
Royce