The configuration of the Subversion interface needs to be done in the cms section of PKitConfig.xml (see example configuration below).
<cms>
<cms-type name="Subversion" factory="de.methodpark.cms.subversion.SubversionFactory">
<cms-host ident="cms.exmaple.net" name="https://cms.example.net" displayName="Subversion Server">
<cms-property name="user" value="username"/>
<cms-property name="password" value="secret"/>
</cms-host>
</cms-type>
</cms>