Merge files into multichannel

Hello! I do quite a bit of work with a program called QLab that uses multi-channel files extensively, up to 24 tracks. It is a pain to render these files and the excellent utility SoundFilesMerger has been abandoned by the dev. It would be fantastic if there was a way to take some number of mono or stereo files and convert them, as a batch, to a multichannel wav file while being able to select which channel(s) of that file are headed where.