

bad news is:
Currently changes to specific building types are quite ugly to code so I would prefer if you would model that as city property changes instead.
These tags are now available for event triggers (please test them, I coded them during business travel so they are not very well tested):
PrereqMinProperties - for a city event specify minimum property values below which the event cannot trigger, e.g. crime rating > 100
PrereqMaxProperties - same but specifies maximum property values, e.g. crime rating < 100 if you don't want a high crime event triggering in a low crime city
PrereqPlayerMinProperties, PrereqPlayerMaxProperties - the same but also works for non city events and the restriction applies to the accumulated property value for a player.
New tags for events (should also display in the mouseover over the event choices):
Properties - changes properties in a city for city events
PropertiesAllCities - changes properties in all cities, works for both city and non city events
PrereqMinProperties doesn't do anything

I have it like this:
Code:
<PrereqMinProperties>
<Property>
<PropertyType>PROPERTY_FLAMMABILITY</PropertyType>
<iPropertyValue>500</iPropertyValue>
</Property>
</PrereqMinProperties>
and it triggers regardless of flammability - I have now added python callbacks just to get it out of the door for now.