I have also experienced this problem. In my case the error message "...run with admin priviledges" appeared when a valid system BCD store did not exist.
(Background info, I was running it from a winPE bootable dvd, and the system hard disk had no BCD store. Microsoft's bcdedit tool gave an error message that bcd store did not exist).
I found a work-a-round by pointing Visual BCD at the store location I wanted to edit eg. running from command prompt: "C:\Program Files (x86)\Visual BCD\VisualBcd.exe" E:\boot\BCD
You could try a similar command, but change paths to match your system.
Seems a bit strange that it gives an error about admin priviledges when the problem is caused by it not being able to find a default BCD store.