My forehead gets these pesky little pimples all the time. So I have been applying a good layer of bp, waiting for it to absorb, then aplying another generous layer. The rest of my face can get away with just using one, but my temples and forehead are really annoying. Is it too much to apply a second layer? Could it build up and possibly block pores, or should it be okay?

The more BP you apply the better. I haven't had anny issues with blocked pores using BP. Infact, when I get a spot, I usually apply more BP to that area.

As long as the BP you're using doesn't contain pore-blocking ingredients, you'll be fine.