Thank you for your question.
At the first, our project have a big history. We have 1000+ customers around the world.
Is Flashengine able to load flash.ocx from any stream? No. Flashengine isn't able to load flash.ocx. For example, it means that you can't make your own flash projector.
Does Flashengine still save SWF into a temporary file before loading? Yes. Flashengine saves SWF before loading.
By the way, Flashengine violates Flash(TM), which is a registered trademark of Adobe. Serious bussiness doesn't make such mistake.
Flashengine is a bad choice, becuase all these things mean that Flashengine is just a "student homework"
About price. We are planning to increase the price in the future. I don't think that the price is high.