Karras' Diary help, please

[Terry Pratchett]

Yes, I know this is an old one, but we've just got broadband:-)

I've got most of the objectives, but still have not got into the church.
Is there an actual key to be found? Likewise, does the North Gate need
a key-cog? Or should I be thinking of something else? Just hints,
please!

I'd also be very interested to know if there's anything worth having on
the ledge visible on the west sight of the 'entry' square. I'm trying
a route to it over the buildings -- I'd hate to think it's going to come
down to box stacking!
--
Terry Pratchett

[Spud]

Yes, there is a key - try transmutation. Likewise, yes it does. Put
the diary in place and look around.

Yes, there is - most people resort to stacking, but some claim to have
found an alternate route.