The Comstock2 is basically the same Comstock scoring, but with additional options to customize target fields (really the scoring zones) to support the needs of several shooting sports, including IPSC Shotgun, Rifle, USPSA Multigun and even PCSL.
It allows to define targets without some of fields (e.g. IPSC A4 target with only ACM zones, clay target with only AM zones, etc). For Hit Factor matches the only recognized target fields are A, B, C, D, M, NS, NPM.
It also allows to specify additional multiplier value for a given target field, to support difficult targets that have x2, x3, x4, etc value. Currently the fractional multiplier values are NOT supported. The apps allow you to enter values like 0.5 or 1.5, but you are going to get some weird results if you use them in a match.
Admittedly the current “Modify Targets” screen in a Hit Factor match allows multiple ways to shoot yourself in the foot. Mainly because Hit Factor match type historically is much more restricted than other types that are using custom targets (e.g. NRA Action, Bullseye, ProAm, etc.)