Licensing, registration, ...

Additionally to the answers Gilles provided for you - I always think it is a good idea, for Windows (I would like to run a Linux-computer, but that's a thing of the future after a few hard hours for me in the dim and distant past 2005^^) to make an image of your c-drive. I keep C clean and small, and use a software called drive snapshot which even is free for 30 days use (to make your backup, restore is free for ever). I bought quite some challenge/response = activation software, and if my windows crashes (alas, it never happened since ages^^) I can simply have a coffee and let my image software restore the c-drive. All of your once and legally or course registered products will still be there after restore .
Just an idea. There is free image-software, and expensive products. The tiny small "drive snapshot" is, besides pianoteq of course, the best I personally ever bought (39 Euro if I remember right). I hope it is okay to post this, I am not related to the devs and just write it because I like the idea, and it is far better than microsoft's own "system restore".
So after one installation on your windows system you could restore pianoteq without any re-activation.

You can (see FAQs, I didn't know that before) also delete activations once your machine has gone to meet its makers (=doesn't work any more^^). So you always got 3 possible activations. Quite a nice thing!

Have fun with Pianoteq, and rest assured, it is no unuseable junk. It's more like piano-heaven .

Probably won't happen, because Pianoteq is based on JUCE framework, which supports Win, OSX and Linux.

Another question:

It says i can install on 3 different computers. How does it identify the machine(s) on which it is installed, specifically on linux? Does it use the computer's hostname, or some kind of profiling of the hardware? What if i change hardware in this computer, and for some reason i need to reinstall pianoteq afterwards?

I ask this because i have a laptop which i intend to use with pianoteq, but i will certainly replace it sometime soon, not sure when. I also intend to update this machine, probably changing most of the hardware in the near to mid future, but keeping probably 99% of the data, and keeping the same hostname.

What kind of trouble can i expect this to cause?