There shouldn't be any actors aside from themed ride staff, previous Merlin attractions have proved that they are just not sustainable in the long run and the attraction will feel incomplete if/when they are cut.
Regarding the Ghost Train, I have a theory. Loggers site was closed for construction, and the DBGT warehouse houses nothing more than the start of a tunnel (seen in the recent promo video) which leads to the CCR station (which will be boarded up), from there you go round the old railway route with VR goggles on.
Okay, maybe not but it's an idea!