If you are just copying the llb, you need the development system on the other computer. (Run Time is irrelevant).
Is LabVIEW allowed to access the folder/file? Maybe it was created by a different owner. Does it work better if you start LabVIEW as administrator?
Is the convoluted story about llb relevant? I.e. does it work correctly If the vis are in a plain folder?
Is the path a diagram constant or formed dynamically? How?