You should only need a 5/64" and a 3/32" to take the housing out. Leave those Torx screws alone, they are pressure lines.
The magazine well screw is to prevent people from putting the magazine into the receiver backwards. They don't always get put in, it is required on all guns we send to the govt just because I don't trust them to figure out how to install the magazine.
The hammer's color is due to a heat treatment. Last two batches had something change the color, we don't call out the final color since it had no effect on the operational side of things. Plus I like red and reddish things better anyway.
