1 CUE, 2 BINs? How do i merge?

[Double44]

Downloaded a European version of Castlevania Symphony Of The Night.. and I gotta say, this game is locked down



After converting the bin.ecm with ECM Tools, the APE with Monkey's Audio & WAV to BIN, and retrieving the CUE from Cues and Sbis :

I end up with 1 CUE and 2 BINs

I've been following this tutorial up until this point. How do i merge these 2 BINs using IsoBuster?!?

Everything is explained well until around step 5-6. IsoBuster asks for the cue, but after selecting the cue, it also wants me to "Find the storage file"?? I select the first bin, but am unable to select the other. Directions state to begin extracting, but what about the other BIN? I continue following directions...

...and am given this error message from IsoBuster:


I close IsoBuster and try again, this time opening the CUE and the other BIN:


Grrr! ..what do i do with the CUE and these 2 bloody BINS?!