2 weeks after the app went live and had received many positive ratings a sales person from Appcelerator contacted the agency saying they needed to purchase a commercial license or the app would get pulled from the app store. (£5000)
While there was some going back and forth discussing this, Appcelerator contacted the end client telling them they also needed to purchase a license (£5000) (full post)
Apparently, this sort of behavior is not entirely unknown from the UK Appcelerator sales team. The accepted answer clarifies the licensing for the App Explore product:
To be crystal clear here, our intentions are that we will not charge for development that happens under the “App Explore” product (i.e., the free version). Usage of the Appcelerator platform (Titanium Mobile SDK, Titanium Studio, Analytics and Cloud Services) at this level is permitted for all applications, both commercial and free, with no financial obligation to Appcelerator. (full answer text)
That answer is from Jeff Haynie, Appcelerator CEO, so it's pretty definitive. It sounds like he needs to reign in his UK sales team a bit, but 98% of Appcelerator customers are not paying licensing costs.
I'm still a fan.