I have those gauges on my Legend. The weren't all that tricky to install. Those gauge faces are designed to slip directly over the needles, so that helps prevent breakage.
I'm guessing that the reason for the 'bug eggs' is due to the stress at that section of the gauge face. That burnt spot is the exact location of the electical connection tab. Without shaving some original plastic off the backside, your gauge plate will bend the gauge face a little too much, hence, stretching the metal conductors inside the face and therefore creating excessive heat.
And yes, the directions did suck.
Tip from experience: if you do get these gauge faces, they need to be glued to the original gauges. i used some plastic adhesive (applied to both surfaces). when gluing, try to keep the glue/adhesive away from the needles...lol...i had a sticky tach needle due to my sloppy adhesion job. thought it may have been faulty since i did tamper with it to install new faces. just a tad too much sticky stuff.