Might I suggest you offer some more detail in a polite way of what the developer can improve on? Im sure that will help the developer to look at the problem and see if he can improve it.
I could not get the hang off the unwrapping in Canvas for a long time... in the end I mastered it you just need to get use to it.
There could be some improvements alright, but it still works a treat. You just need to know what your doing with the tools you are doing it with) One thing I didn't like about it was; when I was unwrapping models, say there was about nine parts to unwrap, as I got closer to the end of unwrapping the first parts of the meshes/unwraps were getting very blurry, making it a little harder to paint. I use UltimateUnwrap now, but still love 3DCanvas to do my modeling)