How did you configure the virtual ESXi host's virtual disk (size)? Since this is a lab, you may consider to use thin provisioning for the Appliance, otherwise you's need a datastore on the virtual ESXi host with at least 90GB free disk space to deploy and run the Appliance.
Btw. don't miss to take a look at vSphere 5.1 vCenter Virtual Appliance and vSphere Web Client Video Tutorial Series | Tech Blog
André