I had a really good play around on my machine last night and finally I think I got to the eureka moment and have figured out a way to get past the problems I was having with the free machine zig zag.
First up I switched on to a new piece of fabric and put a heavier stabilizer behind. Janet suggest pelmet vilene but as I didn't have any of that I went for a bit of TimTex that I had around for postcard making.This did seem to help and I certainly didn't get as much puckering and pulling but I was still having problems when stitching the big razzle dazzle cross down the middle, I couldn't seem to get the tension right and still had some thread breaks. So I switched out the thread and changed the stitch size and the second set of stitching across the bottom came out like a dream.
I then had a few more problems when I switched thread and stitch setting again for the lettering I started at the top. Anyway to cut a long story short after a process of elimination I figured that Beatrice can only handle the free machining on one of her zig zag settings.
Just out of interest I went back to the first sample with the nappy liner stabiliser and stitched out a few letters, and there is a lot less puckering now I've got the stitch setting right.
These two pieces will go in my sketch book as they are, but now I'm going to start a third which will hopefully be my final sample. My original idea for this was to use only threads in red and orange shades to provide a contrast to the blue and greens in the backing fabric. But now that I have figured that I can only use one stitch width I think I am going to make the stitching a rainbow of colours to add interest to the piece that way. Lets hope I really have got to the bottom of the problems and the next piece works!