RE: the 30 knot day...
After looking at your photos, and reading the posts from the other guys, I have more questions than I can develop answers to.
First, what precisely is the problem you are having getting your back foot into the strap?
Have you ever been able to to this (get in the back strap) in any sort of conditions?
As far as getting into the back strap first, some people actually do that, but I tend to agree with Phil 104 that learning to get into the front strap first is the preferred method.
Because leads to a "progression" as you move back on your board.
Once you have your front foot in the strap you are "anchored" and can take your time getting into the back strap.
Also, the back strap first method may work in super high winds, but you will soon be learning to waterstart, and you can then put both feet in the straps (if necessary) before you show the sail to the wind and once you are up, you will be in both straps. This is a very "extreme methodology" but when you get stuck out on the water with too much sail/fin/board, you do whatever works.
As for analyzing your photos, part of your stance problem is simply the fact that you aren't in the rear footstrap.
If you were in the back and outboard footstrap it would turn your body more parallel with the boards centerline, help to sheet your sail the rest of the way in and rake it back so you get more lift to slide your board over the chop.
The bent arms are not good, and indicate to me that you aren't committing to your harness, but when you get in strong gusty winds, we all do it to one degree or another.
Also, since you have an older rig, which wasn't made to "twist off at the top" you power in the sail may be higher in the sail and perhaps a bit further behind mast.
As far as the surface conditions, and what that means, you can really find virtuall any sort of surface condtions when you are that close to shore. The geography and wind direction can combine to make it a true 30 knots in very flat water (the speedsailing sites in Australia and France are good examples) or 30 knots in waist high chop (in side onshore conditions like o2bnme's soundside Hatteras photo).
So, most important, what keeps you from sliding your foot into the back footstrap?
Hope this helps,