[EC900]

The window frame felt seal or the full door weather seal rubber was replaced?

Windows - Try a little silicone inside the channels, they’re probably dry. wipe a little on the sill seal where it meets the glass too. If the new sill and frame felt seals are tight and stressed , then that could be why the motor is struggling.

Are you experiencing the same with the door open with no pressure on the glass?
If the entire door weatherstripping surround wasn’t install just right it would be difficult to close the door or it would stick out a tad, maybe a section is a bit off the track or slightly misaligned in the corners would be my guess.

The window frames are pretty sturdy, but you can try to tap the window frame sides outward with hand pressure a bit if they were bent or twisted somehow, sort of like what would happen when slamming a door shut using the window frame to swing the door shut that could cause some of the frame to distort.

Post a picture.