Your "Profile" is where your settings are saved (i.e. What files to scan, what to do with an infection, etc...) when you change a setting and exit out of the program, it will ask you if you want to save the changes. If you click "yes", it will update your profile so that next time you log on, it will remain the same as you left it
Did you change anything at all before you scanned (what drives to scan, what to do if infection found, where to look, heuristics, etc..)? If you changed anything, it will save it to your profile.
Yes, Since you changed the current settings, it will save it so that next time you open it up, D: will be unchecked still.