Hi again guys. Thanks for all of your advice, but it doesn't seem to work for me. I've updated to 0.12, but the transactions are still stuck.

Look at this one, for example: https://blockchain.info/tx/4c6a6058ba14bff85323d50844ca52d4a25ffa72464555184568888f8480c7e2

It's high priority, "very soon" to be confirmed, but it's been like that for a couple of days now.