Tonight I completed all the hardware for the laser cutter and confirmed that everything is working! I fixed the little issue with the X axis by cutting off the offending portion of the platform support and then retaping the entire platform back on to the moving sled. Also, just for fun, I engraved drawMrSmiley() on the bottom of one of the MDF supports. It engraved quite nicely.
I also made some workpiece holders out of small neodymium magnets and hardware nuts. I saw this idea somewhere online - it wasn't my invention. These will hold nicely on to the sheet metal platform and hold down the workpiece so it doesn't squirm under the intense heat of the laser. :)
As you can see, the magnets work quite well. On the right are the seven drawMrSmiley() pieces of cardboard I engraved as a sort of stress test. They all came out quite well and none of the electronics got too hot. I ended up giving them to friends. With the cardboard engraving, I noticed that if I set the speed to be too fast, the laser would sort of "skip" parts of lines because it didn't have enough time to fully burn the path.
I also made a really awesome looking bookmark by cutting (rather than engraving) blue craft paper. I used some "for" loops to iterate through the area of the bookmark. The laser cutter ended up making 900 holes. Heh heh heh. I like this machine. :)
So, all the laser cutter hardware is complete. I am extremely happy with how it turned out! I also am looking forward to further enjoying its surprising cutting capabilities. The tiny laser packs a punch! Looking into the future, I will be starting to modify the downloaded code that reads gcode and moves the motors. It shouldn't be a very hard task.