Before you go too much further, you might want to run through
this part of the FAQ to make sure you're on target and haven't overlooked any important considerations.
See
here to figure out the number of inputs needed.
At a glance, looks like:
8 - 2 joysticks
14 - Player buttons
8 - Coins/Starts/Pause/Exit/Load/Save
----
30 inputs
Which just happens to match the number of inputs on a 2P Xin-Mo.


Piggy-back the flippers and plunger/ball launch like Malenko suggests -- search for my posts containing "MagnaSave" for more details on wiring pinball flippers "backward" as shown below. (The "impossible" keypress combos that JDFan mentioned only send unique outputs with the KADE Extended Mode firmware, not with Xin-Mo. Improved Extended Mode diagram and description
here.)

PROTIP: Don't use normal microswitch pushbuttons for flippers. (too much hysteresis) Goldleafs are much better. I've also heard lots of good things about the GGG Class-X with True-Leaf Pro, but haven't picked up any to confirm those claims/observations yet.
Before you choose which gamepad buttons to use for the flippers, load Future Pinball and check the defaults for the Pinball Wizard controller -- many tables are designed to be compatible with that controller.

Scott