Paul R. Potts
Installer VISE has a good reputation as one of the best packages for building installers, but apparently that is not saying much… it is really pretty awkward to use, and the documentation is weak.
It is like writing a program in a conventional language where all the actual behavior is hidden. Like: what the conditionals actually say; how comparisons are done (what constitutes true and false); not being able to evaluate any kind of previous step for success or failure without introducing a superfluous variable test item; not being able to actually manage types and perform type coercion yourself; not being able to actually manage strings yourself… ugh.
It does supply quite a bit of behavior for you, though, which would be quite awkward if you had to write it all yourself. Oh well…