Hello,
Just a couple of points:
1. What is the course you are applying for? Considering you changed your program I think it's CS but is it a research based course or taught program? This will help in determining how much of research based knowledge is important to demonstrate.
2. Any sort of experience is valid. The first example could be useful to convey the message why you changed your field of study this way if someone reading your application wonders why you changed?....could say practical experience etc. shaped your decision and it wasn't just impromptu. May be cut this part short only to give a brief of your old background but highlight mainly the skills you picked up during the course which is valid for anything you may do in future.
3. Don't undermine your potential, rather glorify it! So highlight the work you did rather what you didn't!
Hope this helps!!
Zoe.