Versions: MHQ 3.15 & MM 41.5 PLUS MHQ 3.21 and MM 41.11
MHQ 3.21 doesn't handle the import of a MUL file generated from MM 41.11 IF ARTILLERY SKILL IS USED.
MHQ 3.15 using MM 41.5 MUL skips over Artillery entirely.
A 4/5 pilot with Artillery 4 will not import in 3.21. In 3.15 it imports as a 4/5 pilot with no Artillery skill.
Reproduction: Open the 321Test.cpnx (empty) and try and import the 321Test.mul FAILS
Repeat with 315 works but Artillery skill is skipped.
While we could and probably should import init bonus, command bonus (tactics), toughness, and SPAs, there is a problem with importing artillery. The MUL parsing code in MM sets it equals to the gunnery skill if it's not explicitly stated in the file, so in cases where artillery and gunnery are the same there is no way to know whether the MUL file actually gives a value for artillery. I don't know how changing this behavior might affect the option of using a separate artillery skill.