If you want to use HTML5 in the same way as Flash (and also still be able to output Flash from the same editor) Digital Workshop have just released Creator v9.5 which gives you the best of both worlds...
Creator Product Page
We're offering 20 copies for Flash Kit members at £30 or $50 on a first come, first served basis. Simply click any link on the website to buy the full version and then use the voucher code: C9FK632.
Enjoy.
Paul
