The Settings screen must be filled-out first in order for RCDBM to work properly. The available settings are:
RomCenter path: The path in which RomCenter has been installed/placed.
RomCenter databases path: The location of RomCenter's databases (relative to RomCenter path).
RomCenter command-line executable: Should be “rc.exe”, which is the default. No path must be set here, just the executable's name.