I am dividing a single DFM instance into two instances as GreenFields ( new install; no DFM database import/export ) and the original has a number of custom reports.
how can i export them to the new hosts?
You cannot. You will have to recreate the custom reports.
Is there documentation on how to migrate everything to a new server? i am building a bigger/faster server and i want to migrate everything to the new server including our RBAC settings.
Migration is just creating dfm backup and restoring the same in the new machine. This will give you all the settings of dfm you earlier had.