Oh, you can't just include them together. Because they were created as two separate song files, they each contain the extra waves and vibrato table. You can just put all that stuff once at the end, and include the song data.
You will likely run into this HuC/PCEAS problem where if a pattern hops banks, it drops off and dies. I will fix that now and send a new version for you so the CPC song doesn't lose bass near the end of the tune.
It seems this problem only exists if PATTERNS skip banks. If the actual channel data hops banks (which patterns to play, etc.), it doesn't goober out.
To fix it, I basically just cheated and put dummy data where the break was occurring to push the pattern that was breaking into bank 2, so the pattern that breaks now is a big block of rests that mean nothing and are never actually used.
padding!
Check your PM. I sent the updated MML file for you.