M291 R"Home Y" P" " S4 K{"Test","Skip","Cancel"}
if input == 1
    M99
elif input == 2
    abort "Test cancelled by user"
G28 Y

M291 R"Home X" P" " S3
G28 X

M291 R"Home U" P" " S3
G28 U

M291 R"Was Homing OK?" P" " S4 K{"Yes","No"}
if input == 1
    abort "Error: Homing failed."

G1 F18000 Y-999 X-100 U100