I have a problem with my newly installed Eclipse. Whatever plugin I create or import, as soon as I press launch button in overview tab, another eclipse application begins to load which is a full feature eclipse application and nowhere close to my plugin. Did you ever face the same problem in your eclipse v.4?
You can't just run a plugin it has to be run in the context of a RCP with all the other plugins necessary to run Eclipse code. If you aren't writing your own RCP then the complete Eclipse is used. Your plugin will be part of the run.