Since they don't offer any custom support and, even more odd, won't keep a list of developers who suppor ttheri product, the only option is to go outside. We use Evenbooking from joomdonation.com. It managed events (free or paid) and has ALOT more settings. When you see how much information is needed to set up even a biasic event, you'll understand why JS won't support it. It really needs to be a separate plugin. Eventbooking takes some getting used to since there are so many parameters and it may need some custom CSS depending on you template, but in the end it has way more flexibilty. Not an ideal solution, I know, but ultimately you're barking up the wrong tree here. They won't help. Happy New Year to you as well!