Complicated indeed! I think IRS Notice 2007-7 may be somewhat helpful.
Austin - doesn't 1.401A-1, Q&A-4(d) answer your first question if it is a spousal beneficiary? The 5 year clock doesn't restart.
As to a non-spouse beneficiary, they can roll over to an inherited IRA, as long as it is a DIRECT rollover, as per IRS Notice 2007-7. The inherited IRA treatment if the non-spouse beneficiary under 408(d)(3)(C) means, I believe, that the "normal" rules apply - that is, the beneficiary may NOT treat it as their own IRA for purposes of minimum distribution rules, and they can't roll it into their own existing IRA.
So, for RMD purposes, the non-spouse beneficiary who rolls it to an inherited Roth IRA account, as per 402(c)(11), you look to IRS Notice 2007-7 - see IRS Notice 20078-7, Q&A 17-19.
There may be a good writeup of all this out there somewhere, but I surely don't know of one. What little understanding of all this garbage I gleaned only after considerable (as the British might say) "mucking about."
Link to 2007-7 - https://www.irs.gov/pub/irs-drop/n-07-07.pdf
P.S. - and it ain't like I feel totally confident in this stuff - if it were a real situation I'd have to spend a lot more time...