I hate that
I hate that kilns come with these pre-programmed schedules. They provide a false sense of security and are the culprits behind a lot of ruined glass. The kiln is the most important tool a glass fuser has – learning how to adapt firing schedules to a project’s specific needs and your exact desired results is the best educational investment you can make when working with this medium.
Sorry to hear your plate broke.
Regarding fusing the piece back together – no doubt you can do it but it is hard to make specific suggestions without seeing it. Any possibility you could post a pic?
Helios Kiln Glass Studio