2
You need a travel passport (re-entry permit) and a visa for Russian Embassy. You don't have to explain anything now, but on the GC interview you should be prepare to answer some questions unless you can present a prove that you went back there because you have a sick relative or something like that!
Second, when the time for your citizenship come, you still be waiting longer because all time you where absent from US, you have to make up. And on the interview they might as well ask you why you went back to the country from which you run as a refugee?!
But, I know a lot of people who did that. It's not a big deal.
