Here is the offending floor...
And here is the solution, I haven't insulated as I would need to do the whole floor(not an option at present). I've placed the battens at 300mm centres with the folding wedges about the same. I've screwed through the battens into the concrete, and hot melt glued the folding wedges to the battens to stop them shifting.
Here's the finished article, it now gives me a level area that measures 4.8m(16ft)x1.2m(4ft).
It was also a good opportunity for Luke to have a go at scribing a front fascia piece to tidy it up, better for him to practice on this than an actual panel for a client. As you can see not to bad for a first attempt, but he does need to take a bit more time next time. He's very enthusiastic, and I need to slow him down sometimes.
I'm very happy with this little improvement, and should speed things up a bit with one less thing to worry about. What with my nice level setting out bench, and my level floor I feel spoilt.
Thanks for looking.