Only running the last official patch (1.0.7.4) and I'm not in to trying to figure out changing lines of code. I went to Caladon through Gorgoth pass, brought him the components he asked for and no Mechanized Gun. In fact I went back to $%#$@ Tarrant and bought the real Mech Gun components (repeater rifle and auto loading chamber) and still, no gun. I've advanced time one day outside every inventor about 20-30 times and the schematic doesn't ever show up. Is there a quick EASY way of getting the Mechanized Gun that don't give me flashbacks to college FORTRAN classes?
I think the only real answer is what I ended up doing, download the UAP v091225 and suck up the lost saved games. Supposedly the UAP fixes the Maxim mechanized gun quest bug.
Keep in mind that loading saves from earlier versions in a more patched game is strongly discouraged as it can result in bugs. If you want to buy the schematic but lack the patience and have no cheating morals, download and use the inventory hack.