Please use this document
for configuration file format and add the values there.
Also, is your operating system 64 bit?
Is your plugin directory proper?
You can check the plugin directory using your variables.
Also check
rpm -qa |grep -i percona-server
Component should load when you add a manifest file and just look for configuration file in the plugin directory and start.
If it could not load component, the mysql start should not fail. The component will just be inactive.