I already own the Student/Teacher Edition CS6 Photoshop Extended and want to buy the Design Standard Student/Teacher edition in order to add In-Design and Illustrator to my Mac. My concern is that, since Photoshop is included in the Design Standard collection, will my pre-existng copy of Photoshop keep me from getting a serial number/license on the other two products since I know you can only puchase one product per student? I was just hoping someone could clarify this for me before I spent money on something that I may not can use. I really want In-Design and Illustrator and this is my cheapest route as a student.
There will not be any issues, while you are installing the Adobe CS6 Design Standard, you would not have an option to install Adobe Photoshop CS6 as its already installed.
Alternatively, You may de activate and uninstall the Adobe Photoshop CS6(curently installed) and keep it as a back up and use the Photoshop which is a part of Adobe CS6 Design Standard.