There's no multi-quote button, so I'll do my best to answer the questions/comments. Thanks again for all the help.
1. Yes, I checked the polarity with a multi-meter. Since it lit up using the multi-meter, I would assume...
2. That the LED was not burnt out/bent improlerly/overheated/?
3. I did notice the tab/flat spots in the LED's. I haven't had any problem with any of my LE's LED's being installed all the way down, but I'll take any advice I can to avoid problems in the future, so thanks!
4. I seem to use too little solder it appears... I just try to solder to the point where I get a good joint on the surface I'm looking at, where's it ramps up nicely to the component from the pad on the board and covers the pad completely, and results in a shiny joint. I'll try to use a bit more solder in the future.