Alternate AC rules

Good Day,
This software you have created is great, and though I have only used it a couple weeks, I think its almost perfect for what I need. I say almost because there is one thing that would make it perfect for my group to use to run everything. And of course, that one thing is no small matter. I am hoping you can help us.

My gaming group uses the Pathfinder rules, plus an altenate set of rules for how armor effects attack and damage rolls. It makes armor affect how much damage you take from a blow, not whether or not you get hit. It essentially works as follows:

Defense (AC) = BAB + Shield Mod + Dex Mod + Misc Mod (Monk AC bonus, magic etc.)
Protection = Armor bonus + Misc (magic etc.) + other DR

During an attack sequence, both attacker and defender roll d20. The attacker adds attack bonus to their roll, the defender adds Defense bonus (see above)to their roll. Highest total wins, ties go to the attacker. If the attack is a hit, the difference between the two totals is added to the damage dealt. After damage is calculated, the defender's Protection score is subtracted from the total, and the result is applied to the defenders hitpoints. There is no critical hit confirmation. If for example the attackers weapon crits on a 19-20 and they roll 19 or 20, they score a crit if the opponents opposed total is less than or equal to the attackers. A roll of one is still an automatic miss.

This eliminates touch attacks from the game completely, with attacks requiring a touch rolled as described above.

Combat Maneuvers are handled like this:

CMB/CMD = BAB + STR Mod + DEX Mod + Size Mod + misc

During a combat maneuver sequence, both attacker and defender roll d20. The attacker adds CMB Mod to their roll, the defender adds CMD Mod (see above) to their roll. Highest total wins, ties go to the attacker. If the attacker's roll is higher, the combat maneuver succeeds.

So my question to you is, would it be possible to modify the current way your system works to accomodate the above, say as an option that could be enabled or even an add-on? Even if all you could do is modify the way it calculates the AC (Defense), DR (Protection), and the attack rolls it would be useful, as the damage sequence would be easy enough for me to calculate manually and input.

I understand that there would be a very limited market for such a modification, and would be willing to pay you for the time it took to actually make such changes (though I'd need to know up front how much it would cost).

Thanks very much for taking time to read this request.