ahhh see now I did not say I would not have chosen the UI, I clearly used the term potential UI bug in my original post and this is based on the layout of the controls. Tabs are standard items in MFC which can be owner drawn to be displayed any way you wish, hence why I considered it a potential layout issue because the objects in question are buttons. True tabs don't have a seam at the point of attachment and often the remaining tabs have an outline distinguishing them. Whereas in this case the processing controls appear to be overlayed, which is fine if that is the intention.
I am not criticising the design or trying to second guess the intended design but merely providing feedback to the programmers.