Foundation for structure on bedrock
I'm not a licensed engineer, but I've been involved in building structures, block, skirted, footing with a kick wall. I do have a BA in Industrial Techlology (the guys that fix what the engineers thought was a good idea) twits.. The biggest issue with what you are trying, IMHO (in my humble opinion) Site preperation.  You have to get that exposed rock shining.  Then you need to use cord for leveling so you Identify your site high spots.  A chalk line might help with that. you'll have to try.  Next is your anchoring.  Even if the frost goes down 5' 2-3' anchored into the bedrock ought to be enough.  This is going to require a drill on a platform, one you rent. You will need a 36" carbide teeth, x 1" masonary bit.  I'd get 2, oh yes they are expensive!  Talk to your county engineer, explain this to him, it will NOT go anywhere. Drill a 24" x 1" hole in the rock.  cool it with water, a good flow.  Get your drill on a GFI if you want to live! From the contractor desk have them order a case of rebar epoxy.  you may want the pheunuematic tube gun, save your arms &amp; hands. After this is all approved...

cut 4' sections of 3/4" rebar, fill the hole you've drilled and lived, (after 3-4 hot days) cover them tight maybe a cork.  That gets you to the wine/beer making store. LOL  When the holes are fully dry, use the epoxy to fill the hole, put in the rebar.  You can cut the top off at a hight agreeded upon with your engineer.  Personally, I'd put these every 12".  If they end up being 18" high, then wire tie 2 full length's or 1/2" rebar around the whole foundation, minus the door. You'll make this  then ~12" of foundation, epoxied into the rock, with 12" concrete. If there are specs on your frame for pre drilled spots, use those spacings. Then on the top, drill a 1/4 or 3/8" hole just above the frame line, room for a big 1" washer.  Find the company that still cuts nails, they are tapered.  You slam that nail, just above the washer, and pound the narrow end down. with those 12" footings, it will give you a nice base for a level concrete floor. That thing is NOT MOVING.  IMHO in my humble opinion... but I live in an 1854 post &amp; beam, hand adzed timbers house.  I tend to over build. It really sounds like a fun project.  work out the rebar anchors w/ the engineer, and a poored futting 12" high that has horizontal and vertical rebar. The square nail for the wedge in the locked hole, should top it all off.  Hope this works for you... let me know ok?   JLH