The plant needs more sun but a gradual dying off of the lower leaves is a normal part of the growth cycle. Indoor sun is not direct because regular window glass cuts most of the UV. I agree, as much sun as possible indoors is ideal. Here are a couple of pictures of my plant currently growing on a rooftop patio. As you can see it does tend to grow sideways given enough time, even in lots of sun, and I don't mind the unkempt look myself. The flowers are terminal and leave a dead stem just below when they die off, so you want to prune that part eventually (obviously I am lazy about this).
The plant should be very easy to start from cuttings. Start in soil for the best results.
