Never heard of the "fingers technique" before but if it's not unlocking I would start by replacing the digitizer. If it doesn't get fixed then it should be a harder problem to fix, you might have to replace the flex cable which is very hard.
When you plug it does the charging icon appear or does it go directly to fully charged icon? If it's the second, the ipod is not recognizing the battery wich may be from a bad installation. If it's the first then the battery should be proper installed but the ipod may have a problem in the charging circuit.