I'll have a look at the other advice in a minute, but CDs can do Write-As-Once and write the cds without a gap. Admittedly with cds this means they do have to be locked afterwards, but minidisks are completely different surely. They can be modifed after they have been written. Why not write all the data as a one single track then split where it needs to be split. You can't modify cds in that way, but surely computers can send a message to a md player which will then split the track as needs. Surely as simple as!