Supertrucker has it nailed.
Normally, you would go to the Powercommander.com website and download a map specific for (in your case) TwoBros M2 slip-ons.
Strangely, however, as of the time of this post, Powercommander.com doesn't list one for the TwoBros slip-ons yet. That don't list any maps other than stock (zero) maps for the Gen II Hayabusa. Check it out:
2008 Busa maps from DynoJet
You can bet this will change in the near future.
All that aside.... I don't think I would (personally) get your bike dyno'ed to obtain a custom map for your slip-ons (unless you have money to burn). I've been using PC-IIIs for many years now, and, truly, unless you have a full exhaust system, the ROI for the cost and hassle of scheduling dyno time for slip-ons is pretty marginal. A pair of slip-ons just isn't going to make a massively noticeable improvement (not enough to warrant paying for expensive dyno time, anyway).
Personally, I would just run the stock map until a map specific for your M2s are publicly available on DynoJet's web site. This is the price you pay for being on the bleeding edge of new model ownership.
Others may have different opinions, and will no doubt share them.