Configure the URL of the webapp that contains the information of the users, especially the webapp that possesses the plugin-mylutece, in the file userws.properties :
userws.rest.userAttribute.webapp.url=http://localhost:8080/lutece/rest/crm/user/
Configure the private keys for the signature in the file userws_context.xml :
<bean id="userws.hashService" class="fr.paris.lutece.util.signrequest.security.Sha1HashService" />
<bean id="userws.userAttributesRequestAuthenticator" class="fr.paris.lutece.util.signrequest.HeaderHashAuthenticator" >
<property name="hashService" ref="userws.hashService" />
<property name="signatureElements" >
<list>
</list>
</property>
<property name="privateKey">
<value>change me</value>
</property>
</bean>