EDIT - I just discovered that the real problem was a hard border between the titlebar and the frame. I've enabled coloured titlebars, and everything look fine now.
Mods - feel free to delete this thread.
Thanks.
I am using the current, experimental build of AeroGlass for Windows 10 on top of SagorPD's Aero theme. I've also applied xemnes' Win7 Theme Atlas (http://www.msfn.org/board/topic/170233-aero-glass-themeatlas/?page=37) The application has downloaded the symbols required, and the titlebars are transparent - as intended.
As you can see in the pics below, though, the frames on the left, right, and at the bottom do not become transparent. I have tried using WIN7TBAR's skin instead, but this has the same result - the frames remain completely opaque. Changing the theme atlas doesn't seem to result in transparent frames, either.
Does anyone know what might be going on? Is there a setting I should change, for instance?