What version of LabVIEW and the WSN drivers are you using? This makes a big difference as the capabilities have changed drastically.
Also, why do you you need an array of UInt64's to describe a number that can be described with a single? Are you thinking that you will be able to get more precision? Unfortunately, that will not be possible.
Chris
Certified LabVIEW Architect
Certified TestStand Architect