Please attach a video or screenshot showing the correct behavior and how it currently looks for you.

With the modification in contourlines.addon.render.xml:

With the modification in hiking.render.xml

To help you understand, I'd like to point out that if I change the width values for the Thick, Medium and Thin options in the hiking rendering style file, it works fine and the contour lines change thickness according to the values I've entered.

The bug has been reproduced. To reproduce it, import the custom rendering style Hiking.render.xml. Select it as the main map style, then open Contour Lines and choose the Contour line width option.

On iOS, you'll see the "+" option in list included in the rendering style. On Android, you'll see a standard list without the "+" option.

OsmAnd~ 4.9.0#2909m, released: 2024-08-06
OsmAnd 4.8.0.9

iOS	Android

• we need to reproduce this issue

Testing 1

OsmAnd~ 5.0.0#4211m, Released: 2025-01-23

As seen on the map, the actual data has changed to the Default data (color, width, etc.), but the UI displays the data that is not in the list - the data from the custom style continues to be displayed even after restart.

• Show Default settings after switching from a custom style to the Default (OsmAnd)