Why can't you get the money out via a Japanese bank account? They claim to send funds to those within a few days.
Is is supposed to be easy to get a Japanese bank account if you've, say, never been to Japan, and don't speak Japanese? Honest question...
No, you need some level of residency. Maybe it could be worked around by incorporating in Japan and getting a business bank account. I think Gox can do withdrawals to Polish banks too, but unsure.
You can as long as the arbitrage doesn't always go one way, but you have to tie up additional funds.