I suspect the problem is related to the fact that this extension depends on an old version of the Publication Workflow Application (1.10 and the current version seems to be 2.3 in which Loading... has been fixed), which is where the class PublicationWorkflowRenameListener is coming from. You could try to install a more recent version of this one before trying to install “XWiki Publication Workflow Review Application” but I have no idea if they are compatible (the major version jump is not very reassuring).
Now, maybe you don’t really need this extension and the improvement made to the base one include some of what had been done in XWiki Publication Workflow Review Application.