CCS64 v3.x is case sensitie about D64/G64 filenames. If the filenames are GameS1.D64 and GameS2.D64, you can start the game with the command line:
ccs.exe GameS1.D64,0 -autorun
Pressing Alt+F5 will then attach the next disk (GameS2.D64) as expected, however, using the command line:
ccs.exe games1.d64,0 -autorun
Will also start the game, but pressing Alt+F5 will NOT attach the next disk.
The same is true for short vs. long filenames:
"GameDisk1.d64" is not treated the same as "GAMEDI~1.D64" as far as Alt+F5/F6 is concerned.
This should be an easy fix.
The GameBase Collection:
Based upon CCS64 v2.0b compatibility.