Hi,
I`m using RS-BA1 (also N4PY CAT) and IC-7600 for over one year now, without remote utility.
Settings on IC-7600: COM 2, CI-V adress (Radio) 7a, CI-V adress ( RS-BA1) E0, Baud 9600, remote-utility no.
First make sure RS-BA1 is running via USB-cabel to IC-7600 locally.
For the RRC`s serial setting you can use COM 2 logical parallel with COM 0. I prefer COM 0 with levelcontroller RS 232 to TTL on control and COM 0 on radiosite TTL to CI-V IC-7600. So COM 2 still is free.
73
Willi