I would like to test out the new features in RoboHelp10, but I have existing work going on with RH 9. Can I install the trial version as a separate application and maintain my RH 9?
You can. However, when you install RoboHelp 10, clicking the XPJ will launch Robohelp 10 and not RoboHelp 9. Best practice is to keep RoboHelp 10 separate, for instance in a virtual machine.
Adding to Willam’s advice – watch out for the “headless” version of Acrobat that can get installed along with RH if you’ve got an already existing copy of Acrobat in place. Best practice is to try out new software on a separate non-production machine or virtual machine.