D'OH! Firefox ate my first reply.
Shadow Veil req's monk 6; you could do rog 13 / monk 6 / <splash> 1, but in that case you're in the same spot as my original build, with the same problem: namely your Assassinate DCs will be 8 below what a pure rogue gets (7 for non-rog lvls, 1 for not having +2 INT capstone). There's no way you can make up that difference.You're also a lot more feat-starved than my rgr-6-based build was: monk 6 grants 3 free feats, but you'll want to take at least Master of Forms and probably 10K Stars; rgr 6 grants two melee & four ranged feats free, with no pre-reqs for the PrEs anymore.