Did you install Quest 4, already? If you did...
Just go to
the text adventures website (or whatever website with Quest games) and download one.
For example, you might want to download The Things That Go Bump In The Night. You'll have to press the link that says "
Download this game to play offline".
This game (and some others, too) might be in the .zip file. You'll have to simply unzip it with any zip tools you have, for example -
WinRAR. Or, if you don't want to spend any money,
7-Zip is good. Personally, I use
IZArc. Anyway, the WinRAR trial
never ends, so you should probably get that... Well, whatever. Don't mind about these. Just pick one. XD
Anyway, just
Extract the files from the zip folder and choose either the .cas or.asl file that comes with it. It might be even a .exe file. But it's mostly a .cas or .asl file, anyway.
That's it, hope I helped.