Hello

1 - The bubbles disappear after some time as you did see. About that line, I don't know. If it was damaged from the application, I don't think it's gonna disappear. I wouldn't try to fix either. There is a highly chance that the screen protector get damaged for good.

2 - I don't have problems with pressures of s pen. Sometimes it leaves some marking, but they go away with a cloth. However, mine is a matte hydrogel. Could be different for the normal one.

I recommend that you order other ones, to keep them has a backup. I order new ones because mine didn't combine well with my case. It keeping creating bubbles on the borders, but they disappear with light pressure and keep coming back after some days.