So I did some experimenting with your icon, but whatever I do, the icon is always rotated 180 degrees in the taskbar and I can't figure out why. Maybe it is a Windows or Steam issue.
Also I think having an actual ico file in your mod folder is unnecessary, unless you want a desktop shortcut of your mod. Otherwise a single tga file is all you need.
I did however figure out that if you create two tga versions of your mod icon, one 16x16 file named 'game' and one 32x32 file named 'game_big', or any name for that matter as long as it has the '_big' suffix added to it's filename, Steam will use the 16x16 icon in the library list and the 32x32 file on the game page (when selected).
I'm out of ideas for now, maybe any one else has a solution? Dang Focalpoint and your oversized icon.