I tried all four patches, and it didn't work - the GB Player item wasn't there, and my character couldn't get down the stairs.
I patched three of the patches - leaving out the wardrobe patch - and everything works!
Any idea what went wrong?
I had a similar problem with the GB Player earlier... I found that it worked if I applied the GB Player patch last. I think that something in one of the other patches overwrites the GB Player item on the table (But don't quote me on that).
Not getting down the stairs though...? No idea. I'll let RichterSnipes answer that.