HI Andrew
The way I approach an error like this may or may not help. But I can tell you what I do. I start deleting large sections of the source. Bottom up. Make sure you create a backup. Once the error is gone and I know the general area. I add the previous section removed and start with deleting smaller portions. After a few minutes I can get to the line that causes the problem. This all said there has been one score ... and only one where I found the error, however the syntax was correct, so I copied the score to a new file and it compiled while the other did not. I spent some time to deal with that, but since the actual code worked saved as a new file, I could only surmise that lily was tired of working on that file, and didn't realize I had tricked her.