The red line is because you have told Multiplicity to put a line around the computer with focus.
I am unsure what that white box saying Multiplicity is, are you able to post a screenshot of it?
Regarding stopping Multiplicity, you can run services.msc and find Multiplicity Service and set it to manual and stop it if you wish. Multiplicity is designed to start with your computer and act as a native feature (it even works from the login screen) which is why it starts up as it does, but changing the above settings will stop it starting up automatically.