I used the simplekml module for python to create the following KML file
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2" xmlns:gx="http://www.google.com/kml/ext/2.2">
<Document id="feat_1">
<Style id="stylesel_0">
<LabelStyle id="substyle_0">
<color>ff0000ff</color>
<colorMode>normal</colorMode>
<scale>1</scale>
</LabelStyle>
</Style>
<Placemark id="feat_2">
<name>Test</name>
<styleUrl>#stylesel_0</styleUrl>
<Point id="geom_0">
<coordinates>12.581811,55.682581,0.0</coordinates>
</Point>
</Placemark>
</Document>
</kml>
But when I load the document in an interpreter, the marker shows as the standard blue instead of the red color (ff0000ff) i assigned. What am I doing wrong?
You are not doing anything to change the icon of the marker in your style definition. To change the Icon use
<IconStyle>