I will be teaching Affinity Photo in my class. I never have more than two students at a time in one month period. I am teaching adults how to run an office, do graphics and create a website. I used to use Photoshop but I believe I will like Affinity Photo even more. My question is this: Can I install just one licensed program on a total of four computers. One in my office and one on my classroom computer and my two students computers. All will be in the same building and all will be using Windows 10 and all are desktop computers.Or do I have to buy four licenses? Thank you!