Glazing Bead?
Hi there! You have an early model of the Silverline vinyl window that attached the keeper to the glazing bead, which we also believe was not a good idea. You can use our 55-015 vinyl glazing for your window sashes. Take a look and see what you think.
The cold weather could be a contributing factor to the issue. You can either wait for milder temperatures or carefully apply heat at the tip that enters the sash. For the bottom sash, we used to place it on a table, align the glazing with the opening, and then use a block of wood and a hammer to gently tap the vinyl glazing, starting from one end and working toward the other. For the stationary top sash, use the same method: start at one end and work your way to the other end.