Lock post for Simple Wordpress

Previously downloading the plugin, i thought this plugin is for wordpress too. But later on i read its for WP MU and buddypress. So hereby my query is:

Can i use this plugin in any way so that i could lock some particular post by guest authors which are published already. Currently author has the power to edit already published post by admin after review but i need that i may lock all or particular post after it has been published and the guest author may loose authority to delete or edit it?

I know using role editor i can remove the power of guest bloggers to edit already published post but since this plugin has that functionality, so is that would be possible to lock some particular post?

Hope everyone may like the idea.

Thanks!!