Quick attempt to fix FOCItemSaver texture dropdown box for players using a lower screen reosultion then 1920x1200 -> Icon sliders instead of a dropdown box:
I did not test it properly but with this version of FCOItemSaver here the settings menu will change the dropdown box to sliders for the icon textures.
This was done without ingame tests so there might be errors in the lua source code.
If no errors appear the icons could not be showing up in the settings menu or the text of the items could not be updated properly at the icon's headline label.
But at least, if its working without lua error, you would be able to use the sliders to choose the different icons and they should be applied to the markers too.