When I use something like
grails install-plugin some-plugin-0.0.1.zip
Grails cli reports
Error installing plugin: Cannot get property 'canonicalPath' on null object (Use --stacktrace to see the full trace)
Workaround is to put "./" before zip name as in
grails install-plugin ./some-plugin-0.0.1.zip
Forum thread: http://grails.1312388.n4.nabble.com/FAO-Plugin-Authors-required-changes-for-Grails-2-0-td3927936.html
For me, RC1 successfully installs a ZIP file plugin, but then can't find the plugin when running "grails compile" and throws an error.
I forgot to mention, I'm using Windows 7, which may be important for this issue, I guess.