Thanks a lot & Cheers!!
It's actually quite hard to explain this in detail... This is why i made a wizard a long time ago...
1) surf to http://www.mocacinno.com/page/feechecker
2) enter the transactionid of the stuck transaction
3) near the bottom of the page, you'll see a section called CPFP
4) this section has (in your case) 2 buttons: one creating a CPFP with the unspent output that went to the other party, one creating a CPFP with the unspent output that went to your change address. Obviously, you need to select the button creating a CPFP with the unspent output to your change address (since you don't posses the other party's private keys).
5) double check, tripple check, quadripple check the transaction, i would suggest not to use the decoder on my site alone, but also run the raw transaction trough a thirth party raw transaction decoder like https://blockchain.info/decode-tx
6) if you're happy with the end result, you need to sign the raw transaction... Open the debug console again, and type "signrawtransaction [therawtransaction". The output will be a signed, raw transaction
7) try a different raw transaction decoder, check for the 100th time
if you're happy with the end result, open your debug console and type "sendrawtransaction [rawsignedtransaction]"
That is really nice of you, thanks! I get the steps I have to do but I don't have the neccessary knowledge to fully comprehend what is happening. With checking the transaction you mean the addresses displayed in the raw transaction decoder?
well, you need to double check that the input (vin) is indeed the unconfirmed unspent output to your change address, then you need to double check that the address being funded by the output (vout) is indeed your address, and that the value is indeed the value of the input minus a rather big fee. You can either trust my wizard and assume that the difference between inputs and outputs is suffienctly large as a fee, or you can manually re-calculate the fee... It's up to you
Moca thank you so much for your kind support! In the end I didn't want to screw up anything as the amount being transferred was too valuable, so I used a paid accellerator service. It did help though to actually learn technical stuff concerning BTC - Your support is awesome - There's a tip on the way for your help. Thanks again mate!