Battlestar Galactica - No Exit

This was a HUGE Battlestar Galactica Episode. This post is rife with SPOILERS, so if you’ve not seen the episode go somewhere else, nothing to read here.
No Exit answered many questions that have been lingering with most of us for years. As the EW review says, I definitely feel like i’ve deserved this particular episode dammit. I sat through years of BSG goodness, and dammit I wanted some resolution. However this episode didn’t give you everything. It answered (or tried to answer) a number of questions, however these are some of the questions outstanding.
Who Nuked Earth?
So on Kobol, humanity was born. 4000 years ago a tribe from Kobol left for somewhere else. These were the tribe that eventually came to Earth. As it turns out this tribe was completely made of Cylons created on Kobol; back then they could only reanimated themselves. These Cylons left Kobol 2000 years prior to the rest of the tribes leaving Kobol, since they wanted to have their own world (which explains why the left earlier and in the opposite direction to everyone else). Over time they learnt how to reproduce without copies. Emulating humans as best they could.Eventually these guys (over the course of several 1000 years) forgot how to do this, because they didn’t need know. The lingering question remained however was who nuked Earth? Was it themselves? Unfortunately this little interview snippet doesn’t really shed much light on that question. For the sake of argument let’s just say that a war began between the Cylons and Humans from Kobol. The 5 Cylons were warned (through the ‘Head’ characters) and so they went off to stop the same from happening to the rest of the colonies and trying to actually live together in peace.