Can't even install vSphere DP? This is not a good sign

Downloaded current 5.1.1 (build 5.1.56.179) of vDP 0.5T ova. 

From C# Windows Client, able to get through the ovf wizard, fails on creation disk 1 of 4:
Unable to access file:
<path>\vSphere_Data_Protection_-_0.5TB-disk1.vmdk.
Unable to connect to the remote server

On the web client, after RDP'ing to a Windows host that had access on port 9443 and installed Flash and installed the client integration plugin (arg), the wizard wouldn't let me pass the Select Storage. I said Next it went back to Select Storage. I hit Setup Network, it went back to Select Storage.

I think the issue here is that the 0.5T appliance is actually more like 900G when thick and the largest datastore I have in this environment is 700G (and yes, it's empty for this purpose).

I am choosing thin provision during the wizard but obviously this isn't good enough for vDP.

From the horror stories in the community forums I'm just going to say screw it.

This is a big issue when I move my production vCenter to 5.1. I'm only backing up 5 VMs with vDR in prod (why? because it's unreliable) but at least I can install (and re-install and re-install) it.