Notes: If the icons don't show up in your menus make sure the .desktop file points to the icon, e.g: Inside Python2.7 .desktop file locate the line Icon= and replace the value with "python" or "python2.7" (without the quotes). 

So it looks like this: 

• Icon= python - This looks for the SVG file and uses it.

• Icon=/usr/share/pixmaps/python3.3.xpm - This forces the ugly pixelated python icon.

This is true for those menu entries/applications that don't display the correct icon even though the icon is indeed available in the Nitrux theme. If it still doesn't display the icon please report it as missing, thanks!.