I think this proves once and for all that MS cannot improve on code as they often imply, they simply add more bloat, if they did actually make any improvements we wouldn't see the same files being replaced every update, surely they would secure each file the first time around from any potential holes or abuse.
The bloat in programs comes from using third party programs to translate code into the base language the machine uses and worse sometimes its one program converting into another before that too is converted into the base code, this is the " update / upgrade" we hear about but see little of in reality.
The fact that they cannot just whip up a custom program to replace the old xp based variant on these cash terminals is very telling, its not as though they don't have both the staff and the existing market presence to gain the monopoly.