Thanks for wanting to support the Kickstarter! That means a lot to us.
Once the Mac version is released, the HitFilm license will cover both Mac and PC versions. So if you back us at The HitFilmer tier or above, you'll get the PC version as well.
However, do note that these tiers won't be delivered until the Mac version is released around November. But if you're OK to wait until then, this is a great way to get an excellent deal on HitFilm 2 Ultimate.
If you need the PC version RIGHT NOW, then we'd suggest buying from HitFilm.com and then checking out the Badge, Credit and Veteran pledge tiers.