Cysec doesn't usually respond to individual clients. Just make sure to send them all the available information. If you can get someone to professionally translate everything into Greek, that would help Cysec's investigators.
I see you mentioned a branch of SafeCap in the UK closing. What's going to be critical to any case is which branch of the company the money was sent to. If it was in the UK, and if that branch was covered by the FSA, it's worth filing a complaint there.
Since there's a director of the Polish branch, you may want to have a chat with the fraud department of the Polish national police.
Considering the amounts of money you've described, checking out lawyers for a civil suit is another option to consider.