Isn't there some driver/software to hide other partitions?

Yes, hiding partitions is easy, but I fail to see what hiding partitions has to do with it. The setup program is being run from drive C, and Windows 98 SE is running from drive C. The setup program also does not ask me for a particular target drive, but it seems reasonable to assume it is trying to install to drive C.

Whatever you say. My approach was that unreasonable installers can't always be debugged by reason. When it searches for possible drives to install to, it might decide that the possible destination d: or e: or ...
Or the RAM size is too big or or or...

Jorpho just give it a try 😀 You never know...

Very well, I hid the other partition on the disk such that only the Windows 98 SE partition was present. No change.

I also tried running Scandisk. No errors.

It occurred to me I might not have the Windows Installer Engine (instmsia.exe) installed, but no, the unofficial service pack took care of that.

There don't seem to be any relevant switches for setup.exe that I can find except maybe "-z", which causes it to ignore memory requirements. That didn't help either.

I tried Filemon, but the log is a bit of a hopeless mess and it's kind of hard to tell exactly what it is trying to do to determine disk space.

Any more ideas?

EDIT: It occurs to me the package may well have been put together wrongly and that no one can install it.

Specifically, I think someone copied a directory off the SB Live CD, casually tossed in setup.exe , _isdel.exe, _inst32i.ex_, and _setup.dll, and decided to hope for the best without testing it! Not a free space problem after all, looks like.

I definitely remember having to use setver to install live drivers (this would indicate the dos drivers installed in dos - could be wrong)
theres a creative drivers section here at vogons try there

No, both the SB Live! and the Ensoniq AudioPCI use the Windows installer to install DOS drivers. (The SB Live! installer does appear to put setver in the autoexec.bat for some reason.)

I was able to sort out the problem (more or less) with a complete driver CD.

Yea, the SBBASIC and CTCM DOS drivers will complain if not run from MS-DOS 6.22 or older. However for such cards (e.g. AWE64) there is another driver package specifically for W95/W98 users. It's basically a bunch of files like AWEUTIL.EXE and DIAGNOSE.EXE to get the card going. Now resources are already assigned through Windows, so CTCM shouldn't be needed I believe, but could be wrong as I'm not much of a Windows person and prefer pure DOS 😀

Glad you fixed the installation issues 😀