I urge everyone participating to understand a peculiar risk there. First, as Peacefuls pointed out, if you sue Gox Poland for fraud they can probably go straight into court administration mode. Which means a long and untender road until which time the subsidiary will already be tied up into the insolvency storm of Gox Japan. Then, the best case is you will get the measly 5000 PLN. Which, you supposedly should receive anyway given the liable equity capital.
Second, assuming they are in charge of both the deposit account and the EUR account, this would inhibit transactions from there as well. Since people still receive payments from there (https://bitcointalk.org/index.php?topic=489652.0), it shows money is left. Therefore I propose to not sue them for fraud and halting operations, but to apply pressure and negotiate to keep fulfilling their normal business obligations until funds are depleted or official bankruptcy repercussions govern the course of things anyhow.
OP, your thoughts on this? (My sincere condolences, it's bitter times but you will come through eventually).