Problem changing SBSettings icons

Can someone please help me figure out why SBSettings won't recognize custom icons I've configured it with? I've added the SBSettings Tenuis Mod Icons to the var/mobile/Library/SBSettings/ folder, but for some reason, SBSettings only seems to allow a couple of these custom icons to be applied, while some of the rest of them seem to be simply ignored (meaning that some of the icons remain as the bundled default icons instead of the custom Tenuis Icons I've set it up for)...

Any suggestions would be greatly appreciated... Thanks!