If you install a test version of FORTE on your computer, you'll be able to test a fully functional program with all the features of FORTE Premium. You can write your first notes and save your scores.
You will not be charged anything. After the testing period of 14 days, the program just won't open again. Of course you'll be able to access your saved scores when you decide to buy a FORTE license.
The following page will provide you some useful information:
You'll get an overview about the differences between the different FORTE editions.
You'll be able to download a fully functional test version of FORTE Premium.