yes, you can definitely hear original, commercial and innovative music within normal dreams: I'm no musician, but I've woken up with tunes and arrangements of finished songs in my dreams [that sound already fully mixed and recorded] that are as good if not better than a lot of material that has sold well in the real world.

I've only done this about 3 times that I remembered, so I haven't been prepared with a sound recorder to 'sing' the memory of the tune into a tape-recorder or other similar device before the tune disappears forever, but I wouldn't be surprized if professional songwriters and tunesmiths are prepared for when this happens.

I've never tried to write a tune in a lucid dream [it's never occured to me at the time]: the nearest I have got to this lucidly was appearing onstage in a dream and playing guitar alongside Siouxsie and the Banshees [late 70s-early 90s punk/goth outfit] : the only time in my existence I instinctly 'knew' how to play an instrument.....oddly, I had to look at the guitar in order to know how to play it. I even remember the color of the guitar [purple].