I also use a disc install and I have no trouble installing this mod.
concerning your problem, if you are able to run WTW .53 (you know menu screen and etc) then you have installed it correctly but if you are crashing when you start the campaign then this is either an update problem or faulty install (perhaps you deleted or replaced some folders).
I suggest you try to use one of the stand-alone (meaning it does not need base files) submods around here, I am sure there is at least one or two and see if the problem persists.
the base WTW .53 is pretty old/crappy anyway so you are not losing much.