When going through the paramaters of the Variable Flip Angle box of the Concentration curve converter view using the tab key, the two flip angles get skipped.
In general the order by which you can navigate through the parameters using tab keys is not from top to bottom. This is the case in many UI boxes of perfusion/modelfit related views. In this task it is taken care of that the tab key navigates from top to bottom and to the top again once the bottom is reached.