Have you tried the dimmable lamp in an outlet taht you haven't touched? No offense intended but it's possible there's something wrong with the lamp.I used a lamp. I doubled checked the wiring on one of the light switches and found were I had mismatched wires. It solved the main problem of not having power to the top outlet but I still can't get room Bs dimable light to come on.
Also, get a meter. You can pick up a decent one at Home Depot or Lowe's for around $30. If you're going to troubleshoot you need to be able to determine polarity. An easier alternative is one of the light up plug testers for around $6.