Harry, attached modified gtkrc file I currently use.
The icons have the problem is the application icon and icons for mime type files. (\PSPP\share\PSPP\icons). These are the only images generated and are in *.ico format, and the background is white instead of transparent.
If MS Windows do not need a special format. Does the image for these functions can be correspond to the source? (including differences in size of canvas)
Also just noticed that there are two folders with icons ("icons" and "icons-old") and legacy icons are kept in folder.
Attached image showing how icons are displayed (not there is a clear difference between them)
Regards