Running an "administrative account" still doesn't give you all privileges. Only the
system account "Administrator" (which is unable to log in interactively) is allowed to write files protected by the UAC. Therefore, you must use the "Run as Administrator" feature for the PlaneShift launcher while updating. Right-click the "Run PlaneShift" icon on your desktop (or the pslaunch.exe in the installation directory), and select the "Run as Administrator" option in the context menu popping up.
I already created a
bugtracker report suggesting to use "UAC self elevation" (you may know this popup window on a darkened desktop, asking you to allow administrator privileges to an application, blue if signed, yellow if unsigned). But we would first need to find a programmer who would implement this feature.