Building "House" can carry unit "Chuck". Send Chuck to load into House. Before Chuck reaches House, tell Chuck to go somewhere else. House will continue to have the "load" action running despite the fact that Chuck is no longer interested. This precludes the building from using attacks (as it's no longer "standing ground") until it is issued another command. Not a big deal, as you can just use "stop" or "attack_stopped" to fix it, but it's probably not the desired behavior (especially since the AI wouldn't know to do that).
Edit: Also, I'm having trouble getting units to repair a be_built building. Both right-clicking and explicitly telling them to repair the building result in an invalid order. Auto-repair works, though.