Yesterday the SJC issued a change in Me. R. Civ.P. 1 eliminating the sentence that says the civil rules govern the procedure in the SJC when sitting as the Law Court.
The Advisory Note explains that before, there was confusion on the relationship between the Maine Rules of Appellate Procedure and Civil Procedure, and, specifically, M.R.Civ.P. 6(c). Rule 6(c) gives you three extra response days if you are served by mail. Me. R. App. P. 15 incorporates Rule 6(a) (on how to compute time (e.g. start the day after the act, exclude intermediate weekends if less than 7 days), but does not incorporate Rule 6(c).
So, in short, it's now clear that you do not get 3 extra days to file your appellee brief or reply brief (or a response to a motion, or to provide a counterdesignation of the Appendix etc.) before the SJC. Justice Alexander had always said that Rule 6(c) didn't apply in his Maine Appellate Practice (p. 130); now it's officially without ambiguity.
Given the lack of e-filing, this could generate a problem if the other party puts its document on the slow boat to China when a response is due quickly – e.g. a counterdesignation is due 7 days (after "delivery," not service, see Me. R. Civ. P. 8(d)(1), so what does that mean?); reply briefs are due 14 days after the appellee brief. I just had an AG send me something via U.S. priority mail from Augusta to Portland, and it took 5 days.
Usually I send the other side a pdf of my filing and ask them to do the same, which they usually do.
Don't get this confused with the rule in the First Circuit – there, you still get the extra three days, even if they email the document to you. http://www.ca1.uscourts.gov/ (F.R.A.P. 26(c)).