You were only charged for use on one computer, not two.
It shows that you opened it three times and used it for 20-30 minutes each time.
The Panorama X pricing system was not designed with the intention that someone could use it “lightly” for free. If you use it, even lightly, you will be charged a few dollars for a month. So if you use it lightly, you might as well use it a lot, the charge is the same. (If you literally just open it once or twice in a month and use it for a minute then there is a grace period, but beyond absolutely minimal use, there is a charge. This is a business, and it cost hundreds of thousands of dollars to develop Panorama X.)
If you keep using old versions of OS X, you can continue to use Panorama 6.0. Otherwise, you need to take this up with Apple. They decided to discontinue support for 32 bit software – that wasn’t ProVUE’s call.