Can't start RoboHelp5 after I used trial of RH6

Question

I installed the trial version of RH6 on my computer. (Before
doing so, I made backups of my project, in case of non
compatibility with RH5). After the trial period I decided not to
buy it yet and uninstalled RH6, because I couldn't find important
differences (at least not concerning the functions I'm using) and
because the font problem (conversion from Arial to Times, even with
the Adobe patch and after uninstalling alle security updates for
Office) was the same with RH6.
Now I can't start my projects at all. When I try to start the
RH Explorer I get a message, that the registry AppPath can't be
read. I uninstalled both: Office and RH completely, reinstalled
Office 2003, then RoboHelp, but the same problem is appearing.
Even the projects I saved as backup and that I never opened
in RH6 don't work any more.
Any idea what I can do? (can there be hidden elements of RH6
which are not deleted automatically, when uninstalling with the
Software menu in my control panel?)

Answer 1

On my site there is a topic about installing and
uninstalling. In it there is reference to an Adobe topic covering a
full uninstall which does require some registry editing. That was
written for X5 but I think it will cover RH6. I cannot guarantee
that though.
Make sure you create a System Restore point before you start
playing with the registry and only do that if you feel confident.
If not, enlist some help from IT or a developer.