Right now, besides directly editing the config file, the best way to edit the options for this plugin (as well as other plugins by FlashXML) is to go to that site and generate a config file using the options on the demo.
It would be really nice if you could create a similar utility accessible directly from the Admin Dashboard. It would be much more convenient for your users, and we could edit the options easily right in our own WordPress installation.
If creating this feature isn’t an option, you could make a user’s manual instead. In this manual, you could describe each of the available options and detail the available arguments. Not quite as cool as a GUI options page, but it would suffice 🙂