TDI cold starting anything else to try

A friend said the same thing about setting slightly advanced as the timing will retard as the belt stretches, anyway I've set it again this afternoon so its now in between the middle and upper line closer to the upper to be honest I had set it the first time to almost bang on the centre line just a midges on the retarded side, so I'll check again in the morning to see if a little more advance has made any further improvement to my cold start but I'm certainly happy how it started this morning.