Did you open the same workspace the plugin worked in? Am i right?
Meta.inf: How is it created? By builder, or it has fixed content? What
kind of builders do you have in your project? Could you attach
metadata files of your project (.classpath, .project, .settings folder
and the manifest itself).
Cloud not be read stuff: I have no idea. We could modify the plugin to
dump error details. My idea is to dump the marker id of the error in
the log, and the error details could be written to a separate file
having the id as a name. What do you think? I also googled your error
like this : "java could not be read" eclipse. There were some results.
Probably you should check them.