Thank you for the feedback. There is a limitation in the technology used in dushare, it completely relies on UDP streaming which makes it really fast, but not firewall friendly. We are working on a potential solution (fall back to TCP transfer), to be released in the next cycle. Loading the entire file in memory before sending it is a flash-player constraint out of security concerns, it doesn't allow flash-player to manipulate files on the computer directly, no solution found to this problem yet.

and your UI problems are noted, thank you.