After two nights of hacking sessions I've completely rewrote everything, so the development version (can be found in branches) can do everything, what 0.2.0 could do and much more
There are two new sexy features - the ability to override every property for each space (not only space url params) and the late binding for system paths.
There are still some problems with non standard java options (which start with -X and -XX and contain non-alphanumeric symbols), so the only idea is to add them as strings.