Window won't stay up
Hi there- thanks for reaching out!
We'd like to see your window and a picture of where the balance is attaching to the pivot shoe. I've attached some media guides on tilt balance installation for you to review. Hopefully this will help. Please get back to us if you still need help.
Thank you for the photos. Comparing the pins on the old balances and new balances, are they the same size? When the spiral is remove from the pivot shoe, is the opening clear to receive the pin and are you attaching the spiral to the pivot shoe with our 75-006 charging tool? Sometimes that holds the spiral so you can push the pins to lock them in the shoe.
Maybe try filing the pin down. Let us know if this helps.
It's possible. Look over the pivot shoe, specifically where the balance spiral fits into to see if there is something blocking the pins from locking in. From your photos, the overall look of the pivot shoe look fine, so I don't recommend changing the style.