I have backed up the old files before the update, fearing the worse :)

On Win10 there is no performance benefits to exclusive full screen due to gpu scheduling improvements.

The game should still have a rendering resolution slider.

The missing music really sucks. I don't know why they wouldn't relicense it... How.much could old music nobody ever uses really cost?

There was a bug on steam where some of the files got messed up on install and caused music to not work properly. They were selling the soundtrack on steam so if they can sell the soundtrack why would they remove the music in game?
This is the track list from steams soundtrack:
1 Lollipop - Ben Kweller 2:16
2 My Boyfriend's Back - The Raveonettes 2:39
3 Earth Angel - Death Cab For Cutie 3:17
4 Shakin' All Over - Rose Hill Drive 2:53
5 Strangers In The Night - Cake 2:52
6 There Goes My Baby - The Walkmen 2:17
7 Everyday - Rogue Wave 3:41
8 All I Have To Do Is Dream - The Dandy Warhols 2:40
9 Mr. Sandman - Oranger 3:03
10 If I Only Had A Brain - The Flaming Lips 2:17
11 Tears On My Pillow - Clem Snide 4:02
12 Lonesome Town - Milton Mapes 3:08
13 The Living Dead - Phantom Planet 3:27

Yes , there is a soundtrack, but its not IN the game