Sorry to hear that you've having issues.
However, the Velbus log seems pretty clear.
For some reason, your OpenRemote controller can't get a connection to VelServ.
As you've suffered a power failure, my initial thoughts are..
1. VelServ came back up, after OpenRemote. So the connection wasn't available for the initialisation. (If the TCP link fails after initialisation, OpenRemote will keep trying to restore the connection)
2. Your OpenRemote Velbus configuration is looking for an IP address that no longer exists, because your BBB was assigned a new IP address. (This assumes that you have configured OpenRemote to use a local area network address, rather than 127.0.0.1
I would suggest a reboot first and if that doesn't resolve it, then look into the IP address settings for your Velbus networks in Designer.
But at least you've got it working.
I can't remember if the BBB you have is running JVelbusD, or VelServ.
However, I normally configure them to use the same port.
So..
Within the OpenRemote designer, you should set..
127.0.0.1 and port 6000
(localhost will also work)
From your internet network, to connect VelbusLink to the Velbus server on the BBB (or anything else you might use in the future, or for others reading this)
You can use the TCP/IP connection option and enter the local area network address of the BBB and port 6000
Good luck
Stuart