I understand that this software is limited to 24 tracks but it will also not allow me to enter any channel above 24, from the Behringer X32 soundboard, to tracks 1-24. It there a fix for this?

I think the limitation is in the iOS implementation. Technically multitrack is using an audio category in the API called 'play and record' or AVAudioSessionCategoryPlayAndRecord, which I could never get the upper channels to pass audio. There is another category called AVAudioSessionCategoryMultiRoute which may work, but it has other issues eg. compatibility with other apps so multitrack doesn't use it. Unfortunately there isn't much to do about this except file bugs with apple.