Pics? Mike P. has mentioned that you want to use something "chunky", a polishing compound like m105. I know you said you have tried compound, just throwing it out there. :xyxthumbs:
All good.
M105 is not chunky, the abrasives are "super" microscopic in size, it does work but I dont' think it or other micro abrasive product tend to work as good as diminshing abrasive that are chunky.
I've polished a lot of water spots off glass in my life as well as paint but that's because I lived in Oregon... LOL (lots of rain)
Here's something I posted here...
http://www.autogeekonline.net/forum/ask-expert-featuring-mike-phillips/31954-scratches-glass.html
Couple tips on machine polishing glass,
First it's messy. I've used 3 different brands and homemade slurry and they are all messy, by this I mean when using a rotary buffer you can't help but sling a little spatter, so tape-off and cover up anything you don't what to wipe down or detail splatter off of, or out of, after the job.
The glass buffing pads are thin and hard but work well, my personal opinion is to use a backing plate that offers a foam rubber interface for some cushion and ability to flex, like one of these,
Heavy Duty 5 Inch Rotary Backing Plate
The above fits the 5" Glass Cutting Pads.
You can remove light scuffs and scratches but you can't remove deep scratches or chips because to do so would mean buffing and removing enough glass to level the upper surface with the lowest depths of the defects you're trying to remove.
Also, do keep the buffing moving, don't hold it in one place and you won't have a heat problem.