Notable differences for flash games?

Are there any notable differences I would need to know to create a flash game using Unity3d?
I’ve been working with unity for a while and am very familiar with interface, coding,etc. I was thinking about creating a flash game and was wondering what the difference is between what normally occurs and game dev for a flash project.

The Flash platform is still being worked on. There are a lot of features that don’t work yet in Flash because they have not been implemented yet.

See this list of what works and what doesn’t.