As I know Hp will release a migration kit only at the end of August with the release of the 5.1. How can you migrate from 4.5 to 5.0 ? I have no idea how would be the procedure to transfer the CMDB ... Good luck, Rubem
I think your best option is to wait for the migration tools that have been promised when 5.1 is released.
HP have said that 5.0 is for greenfield sites looking to start using OVSD and not sites which have a previous install. Even if you manage the export / import of the database (not withstanding any database differences) I would imaging that HP will not support any issues that you have.