To get the variables that were passed to the AHK Launcher from LaunchBox use these lines of code within your AHK Launcher script:
launchboxPath := param in A_Args[1]
romPath := param in A_Args[2]
platformName := param in A_Args[3]
SplitPath, launchboxPath,, launchboxFolder
SplitPath, romPath, romName, romDir, romExt, romName_noExt, romDrive