Authoring process for a 8cm disc

I am currently trying to create a master disc for a project in DVSP 4 that will be replicated into a mini-DVD (8cm) when finalized. I actually burned the project to a Sony "for Handycam" DVD-R 1.4G and it was sent to China for replication. Turns out they are telling my client that the disc is "not working".

My question is: is this media OK to author to? Can a replication house use a mini disc to master to? They have not specified any special needs and I know from experience at lest here in the US, they take DVD-Rs as a master and fewer are relying on DLT.

This is my first "mini" DVD project and wan to figure out if I am doing everything I am supposed to in terms of using the right media, process in authoring (which I assume is the same except changing the settings to 8cm).

Any help is much appreciated. Client is freaking out. And I am too a bit.

Colin