Hello, QT is something that I have experience in as it is is what I've used to write a game of my own. C++ is my primary programming language and I've taken advanced c++ courses as part of my degree.
Adding user control, score keeping, gamestate, etc is something I've done on multiple occasions so I'm very confident I could get this done. The way I would do this is first getting the user control worked out, then work out the ability to win/lose. Afterwards I would add the 4th thing in the stage 3 list which is the ability to provide score to a user. Then I would get the powerups implemented.
I would work on getting the high distinction.
I hope you consider my proposal, thank you. :)