... you wil need to have a path to DAZ Studio 3 in your dzinstall.ini file - either by editing or by having installed DS3.
This was very helpful, with a bit of flailing I’ve been able to install and access the old docs. And it’s like you just turned on the lights in a dark room!
It was not easy to install, though. The d/l links for DS3 - all the ones that I could find - are broken. I had an old 32-bit DS3, so I installed that. The DS3 SDK still refused - “install path not found”. After a number of trials, I found that what I needed was an entry like this:
dzStudio3InstallDir-64=C:\Program Files (x86)\DAZ 3D\DAZStudio3
in the copy of dzinstall.ini in my C:\Program Files (x86)\Common Files\DAZ directory; the -64 was essential, even though actually being 64-bit software was not; and so was finding the right one of three copies of dzInstall.ini found in three different locations.
To find out how restrictive this is, I tried again on a different machine without installing DS3. When I created a dummy directory, C:\Dummy\DAZStudio3 and added a dummy file DAZStudio.exe, and edited the copy of dzInstall.ini in the same location as noted above, it was enough to complete the install of the old SDK.