Just downloaded it. When you complete the registration section, you need to complete ALL the information blocks, not only the ones in bold (as they wrongly stated). There wasn't anything in the download section about removing prior versions of Office first so I did a web search and came up with:
http://www.timeatlas.com/mos/The_New...l_Makes_Sense/
It seems you don't need to uninstall - see the section by Before Downloading Trial Software. Sixty days full functionality, which seems long enough to decide if it's superior enough to buy.
I'm just about to do a System Restore and run it. Hopefully I won't be back in tears...