It looks like the mod name in the "items.lua" was not updated.
Just open that file and change:
icon = "Long_Underground_Pipes_16/graphics/icon/2xUndergroundPipe.png"
to
icon = "Long_Underground_Pipes_16_fixed_crash_and_icons/graphics/icon/2xUndergroundPipe.png"
for each icon.
Seems to fix the issue.
