Maybe a bit late, but I am missing 83806 Blackcoins. Tried to withdraw them but I was too late, the proof is below....
How big is the chance of getting something back?

You could try contacting the liquidator liquidating Mintpal's assets. It appears to be still ongoing, so you might have a chance to get something back.
I posted this in dogecoin subreddit today:
I contacted the Insolvency Service about MooPay's case and was told this:
If any one has claims, they can contact the liquidator liquidating MooPay's assets to pay creditors (people who lost coins would be creditors in the bankruptcy context): Graham Stuart Wolloff (of Elwell Watchorn & Saxton, LLP - 1 East Poultry Ave, London EC1A9PT, United Kingdom) and/or Liam Alexander (same law firm).
Also, I was told if there were any concerns about the conduct of MooPay LTD or its officers, Mr. Brian Penn of the Receiver's Office could also be contacted (
Brian.Penn@insolvency.gsi.gov.uk).
Again, contact these people if you hope to receive anything from MooPay's assets. Contacting these folks would be IN ADDITION to contacting Action Fraud.
This is the latest liquidator's report dated 23 June 2016.
https://beta.companieshouse.gov.uk/company/09009856/filing-history/MzE1MzA3NzYyNWFkaXF6a2N4/document?format=pdf&download=0The bottom of page 3 says the Mintpal liquidator has not started accepting claims from the majority of people owed money yet.
Any new liquidator reports should be posted here.
https://beta.companieshouse.gov.uk/company/09009856/filing-history