I just created some sys_choice entries for the boolean field I wanted. I set the value to 1 and 0, and the label to Yes and No respectively. Worked fine. It doesn't affect anything having the extra sys_choice entries there. You can even make them inactive and it still works.
I spent more than 4 hours think in a solution for this situation, and I just found complicated solutions. This solution come out like a light in the end of tunnel, simple like the best solutions have to be, congratulations.
