Can you verify plugin.xml in SDK or after export of jar. Extension point entries specified location along with Identifiers might be wrong. Regarding version may be it is something to do with MANIFEST file ?
As a quick check you can start the SDK envrionment server by adding this developed plugin before applying to standalone DEV environment.
- Lokesh Kumar
It was the manifest file that I had left on default option (generate a manifest file) when exporting the jar. Had to select the manifest file from workspace that had all the correct identifiers and version numbers.