MuppetVision, Star Tours, Tower of Terror, Rock'n'RollerCoaster, Voyage of the Little Mermaid and Great Movie Ride are the standard evening EMH attractions at Studios... I would have to assume that because of the proximity of the Osborne Lights display to the MuppetVision attraction, that they'd have no reason to cordon off that part of the park, and you should be able to wander around there during evening EMH.
I can't be positive though, sorry.