I've been getting a lot of questions lately asking "How do I download your program?"
The Tangleword/Boggle solver is Web-based, meaning that you go to a Web page, type the letters of the board into a box, select some parameters from some lists, and press the "Submit". Your browser sends the query to the Web server, which does a bit of processing and sends back an answer. There's nothing to download or install on your computer; you're just typing information into a form on a Web page and getting the result as another web page.
How to use with <Playsite>? The best way is to be familiar with resizing windows. Open both Playsite and solver at the same time by using "File:: New:: Window" to open a new browser window. Resize the Playsite window to take up half of the screen, resize the solver window to take up the other half of the screen, and then you'll be able to view both at once. You can type the board into the solver, press "Submit", and view the result. Then you'll have to type the words manually into the word-entry box on Playsite.
The word-entry box on Playsite disables the "paste" function, so you can't copy and paste the list of words into the box. By entering the words manually (it helps if you type fast) you can score highly. However, there do exist stand-alone Tangleword cheat programs that automatically enter words into the Playsite box. They do this by sending keystroke messages directly to the Playsite window, so Playsite thinks you're actually pressing keys on the keyboard. You would have to download such a program and install it on your computer. I'm not knowledgeable about any specific such programs.