rendering gpx in obf

[mariush444]

I created obf with my gpx files using tool
utilities.sh convert-gpx-to-obf from OMC

These tracks are visible starting from zoom 9 that is defined in default.renderer.xml
I want to see them starting from zoom 7 but I don't know how to do it.
Changing two first lines to "=7" doesn't help.

Does someone has any idea?

piece of original code in renderer file.

!-- GPX tracks in obf   -->
		<switch minzoom="9" tag="route" value="segment" color="$redColor" cap="ROUND">
			<case maxzoom="9" strokeWidth="5:5"/>
			<case maxzoom="14" strokeWidth="8"/>
			<case maxzoom="17" strokeWidth="10"/>
			<case minzoom="18" strokeWidth="12"/>
			<apply_if additional="color_white" color="#ffffff"/>
			<apply_if additional="color_red" color="#ff0000"/>
			<apply_if additional="color_orange" color="#ff7200"/>
			<apply_if additional="color_brown" color="#ba7007"/>
			<apply_if additional="color_darkyellow" color="#afb61c"/>
			<apply_if additional="color_yellow" color="#edc300"/>
			<apply_if additional="color_lightgreen" color="#6cb52b"/>
			<apply_if additional="color_green" color="#00842b"/>
			<apply_if additional="color_lightblue" color="#2ec6ff"/>
			<apply_if additional="color_blue" color="#4e4eff"/>
			<apply_if additional="color_purple" color="#a71de1"/>
			<apply_if additional="color_gray" color="#999999"/>
			<apply_if additional="color_black" color="#000000"/>
		</switch>