Career change from where? Career change doesn't mean you've instantly forgotten all you knew before. Your knowledge and experience may be valuable to a software project being made for the field you used to work in. You might even know some people or at least companies that produced something you used to work with. A long time user of a complex application is often a valuable addition to the development team even if his programming skills are sub par. Less things to explain, lots of experience with the quirks and problems of the current version, ...

Besides ... with the amount of thought and work you seem to have put into your project and your modules I think you don't have to be afraid to apply to a Senior Developer positions.