Last time I removed the wallpaper from my then newly acquired house it
wasn't much different from what you described. What I did was:

1. use a scraper to remove all the glue spots.
2. use drywall compound to feather over all indented area
3. sand all the mudded area flat
4. prime
4.5 at this point, all my mistake from step 1-3 became
pretty obvious and need to be corrected.
5. paint

FC

mikegi wrote:
(snip)
When I scrape off a glue spot, it pulls up the top layer on the
drywall, leaving a brown area. I've tried sanding the spots down with an
electric sander but it isn't going well. I now have a multilevel wall: the
original paint, glue spots, original drywall surface, and brown drywall. A
disaster.

I'm looking for ideas (other than burning down the house and starting over).
I've read about the Zinsser GARDZ and wonder if I can paint it on top of
everything then smooth out the worst areas with drywall compound?

Help!

Mike