[OSM-newbies] building=yes on highway=pedestrian does not render?

[Zeptomoon]

Hi everybody!

I am trying to map two churches and a museum which are distributed on a
larger square in Heraklion, Crete.
Any idea, why I do not get the buildings rendered with Mapnik?
Maybe I got some tags wrong?

Strictly speaking, the area of the buildings are NOT highway=pedestrian.
Do I have to make a relation with holes for the highway=pedestrian area?
I guess this is not the problem. I've seen churches on other areas
before, I think.

Here's the square:
http://www.openstreetmap.org/browse/way/43755404 

Here's the area with Mapnik:
http://www.openstreetmap.org/?lat=35.337529&lon=25.131025&zoom=18&layers=B000FTF

With osmarender the outline of the buildings show up (not the museum):
http://www.openstreetmap.org/?lat=35.33767&lon=25.13088&zoom=17&layers=0B00FTFT 

P.S: Would it be better to connect the surrounding streets to the
pedestrian area? (i.e. merge nodes)

Cheers, ~~~~