A default 3.1 install puts the tool Install in C: but not Installer. They're different 
@Paul81: Ha ha ha! See this is what I absolutely love about the Amiga and Workbench: When you get advice like the good one you just posted to me, you initially think "no way! It can't be that simple". BUT IT IS! Your advice worked perfectly and as @Matt_H wrote above, I did indeed have "Install", but no "Installer".
I copied the Installer from my 3.1. install floppy and VOILA! Now WHD Load is installed and I'm downloading Killer Gorilla and Retroplays massive packs. Looking forward to see just how many (or how few!) games will actually play on my Amiga 600 ;-)
Bottom line is: Thanks for all the kind help!
2 questions:
- Why is there a tool called "Install" and not "Installer"?
- I need to find a good unzip program to unzip Retroplay and Killer Gorillas WHD Load packs. Any recommendations?
Cheers from Copenhagen
Anders