Proper sort by level. possible?

[Marazota]

Hey guys right now there is one addon that can sort items by level
called
Crafting Material Level Display

but it have one issue and i want to help current maintainer to fix it if possible

if i sort items by level from low to high, 1 lvl items will always come after 10 lvl items
no matter what
all other levels are okay and working as intended

any ideas how to fix this?