From what I understand, even though some sources are up for the L preview, not everything is there which limits the usefulness of source builds at the moment.
There is an ongoing discussion of L porting in the general section and even though its for the Verizon gnex, just remove the very top line in the updater script of the zip over there to make it flash on toroplus.
Everything almost works but our open gl drivers aren't up to snuff and that pretty much can't be worked around at this point. Also it won't boot into android even though its about 90% of the way there, but full source is needed to hack around it.
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