I/O repeater app: invert signals?

I am planning to use a wixel pair as remote camera release (for multiple cameras), but I found the logic is kinda reversed when it comes to buttons, and simply closing circuits (please forgive me if this may sound amateurish) isn’t as easy as I had hoped.

closing a button on the sending wixel is making the input pin from high to low, and the receiving wixel will go from high to low also, which is straight forward logic… unfortunately, simulating a simple push of a button requires inverter logic and a NPN transistor on the receiving end.

Unfortunately, my project is very tiny, and adding another board with 2 inverter chips may not work (not enough room inside) (I need to simulate 10 buttons in total).

My question is:
Is there an easy way to invert the logic via software/or editing the i/o repeater wxl file directly?
I.e. p0_2(-1) goes from high to low, and p0_2(1) goes from low to high (allowing a NPN to close a circuit).

I would greatly appreciate your advice.

Or in other words, where in the io repeater.c do I make changes to invert the state of the output?

My wife found the solution for io_repeater.c

155: setDigitalOutput(outPins[pin], (buf[byte] >> PIN_VAL_OFFSET) & 1);

change to

155: setDigitalOutput(outPins[pin], (buf[byte] >> PIN_VAL_OFFSET) ^ 1);

one single character change (from bitwise AND (&) to bitwise XOR (^)) does the trick.