Don't know. The author didn't supply a readme. Guess you'll have to find out yourself. Or, you could contact the author.
Edit!
here is what the author posted on the intfiction forums.
"I just uploaded Kerkerkruip release 2. It doesn't contain everything that I wanted it to contain, but I realised that "release often" is a much better model for me and this game than "release when ready". After all, Kerkerkruip is never ready! Here is what I wrote on the IFDB.
Release 2 of Kerkerkruip has been made available, introducing new features, fixing many bugs and (probably) introducing many new ones. Hours of random dungeon crawling fun for the whole family guaranteed!
New features: more powerful smoke and hiding systems; new scrolls; random dungeon features like unholy runes and a teleport beacon; two new special enemies; the ability to turn into a vampire; a less random distribution of attack rolls; and much more.
If you're new to Kerkerkruip, please check the IFDB page for the accompanying files, like the Beginner's Guide and the instruction videos."
@SLJ: It's a glulx game. It's a text-based RPG.
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