KJEZ:
One tip that has helped me- the swing meter is 10 Cm long so took a strip of paper that long and marked 25, 50 & 75% on it. Tapped it right below the meter- my distances have been perfect ever since.
If you're going to make something like a piece of paper, you might as well make it 15 cm long, and just multiply the distances by 1.5.
25% would go from 2.5 cm to 3.75 cm.
50% would go from 5 cm to 7.5 cm.
75% would go from 7.5 cm to 11.25 cm.
That way you could play with your WGT window sized larger.
If you're decent at math, you can just maximize it, measure the length of the power meter, and then put the marks at the right spots, even if it is, say, 14.4 cm long at that point. (Just multiply the 14.4 times .25, .5, and .75, or whatever percentages you want.)