We've run into an issue with specific characters and the Remote Session Launcher. So far we've run into problems with ";" and "," characters. In the case of the ";" character, Putty will run, but will display the initial page and the Hostname field is empty. In the case of the "," character, we receive an error (sorry I don't recall the exact error displayed) but it turned out to be the part of the password after the "," character.
We've fixed this locally by changing the script by adding single quotes around the password in the ps1 file. Let me know if you need additional details.