Having problems rendering simple things

Hi, I am really new with mapnik and I am having some problems with what I think are simple things. I am trying to change a little bit the way mapnik render my map in order to change the color of different rooms and so on. So what I have to change at first is layer-buildings.xml.inc. I just add one simple style for the elevator room and it crash:

[ref] = 'elevator' &maxscale_zoom19; #37716b 0.8

I have noticed that it is that the one that give me the error, because when I just add a new layer it doesn’t crash. The error that is giving to me is this one:

RuntimeError: XML document not well formed:
Entity ‘layer-buildings’ not defined at line 3478 of ‘osm_23_12_12.xml’

In that line “3478” what I found is this: &layer-buildings;

I am using mapnik 2.1. I guess is a really easy thing but as I am really new in this topic I don’t have any idea on what to do. Thank you very much in advance.

Hi, I have to add that for this Style I have added the next layer in the layer-buildings.xml.inc:

indoor_buildings_elevator (select way,aeroway,layer,ref,name,amenity from &prefix;_polygon where (ref='elevator') and (building is not null) order by z_order,way_area desc) as indoor_buildings &datasource-settings;

Also I have change the lines of CssParameter because it looks like that is for older versions of mapnik, I putted:

And now I think everything should work, but it doesn’t. Please any ideas? thank you very much!

Ok, I think more or less the problem is solved. What I have changed is the &maxscale_zoom19; if I have 18 there instead of 19 it works, everythings over 18 gives me that error, but I don´t know the reason, somebody knows? thank you very much!