Hi,
As you state, Replication Exec (VRE) normally configures a 60day Demo license key at installation time, if no other license is entered. This does not appear to be happening in your situation, as you are getting the "Replication Exec license is Invalid" error. If you open the RMS console and go to the Servers tab, the Properties of the local server should allow you to see if there is a Demo key added. I suspect there me no license shown there.
I am currently investigating this here and will get back to you with any further news.
In the meantime, could I ask why you are reviewing Replication Exec, as this is quite an old product and has had no updates to this released in the last 3 years? The functionality has now been moved to the newer Continuous Protection Server (CPS) that is part of the Backup Exec suite of products and has the capability to do more than VRE can.