How to remove objects by mkgmap style

I am using the mkgmap option --add-pois-to-areas to see all the supermarkets on my garmin. Now I found a way to also see railway stations at lower resolutions. Unfortunately, lots of them appear in the map, although they are only “light_rail” stations (which should be filtered not to show up by my points style). The problem is, that even if ligh_rail=yes is set for the POIs in OSM, there sometimes is a polygon railway station building only with the tag railway=station. For these objects, a POI is generated only with railway=station and a “big” railway station symbol is produced by the points style.

Is it possible to completely remove a polygon (or to remove its railway=station tag) by the polygons style, BEFORE it is translated into al POI by the --add-pois-to-areas option?

BTW: Is there a comprehensive description how to use mkgmap? (This here seems not to answer many questions.) Also the text fragments delivered with the mkgmap-downloads do not explain enough.

In the points file you can use railway=station & mkgmap:area2poi!=true
You can delete a tag by using {delete …} for instance light_rail=yes & railway=station {delete railway}
If you want to know more try to search the mkgmap-dev mailing list:

That is a good idea. Maybe I will test this next time. Meanwhile I tested two other things.

What did not work, was adding the following line to the polygons file:

railway=station {delete railway}

The POI with (railway=station) was still generated due to the --add-pois-to-areas option. It seems that the point is generated, before the actions in the polygons file are done.

What seemed to work was adding the following line to the points file:

(area=yes | building=yes) & railway=station {delete railway}