<?xml version="1.0" encoding="UTF-8"?>
<root>
<error id="main">
<title>Subset not unique</title>
<description>
## Non unique subset name found

    Non unique subset names: '{non_unique}'
### How to repair?

Remove offending instance, rename it to have unique name. Maybe layer name wasn't used for multiple instances?
</description>
</error>
</root>