This makes no sense, ldconfig is a basic tool. You can also retrieve it directly from the internet, just
search for a package here: rpmseek

Get an MD5Sum tool like this one: HashCalc 2.01 for WinXP (Freeware)
or this other one MD5 Checksum Verifier 1.2 XP, Shareware (15 days)

To see how it works, take any of them and verify the checksum of the zips. Md5sums are normally indicated in the download page, such as this one:
http://www.tucows.com/get/414080_155093

Here you can see that the md5 hash is:

MD5 Hash: c692af1c24f633dfe9e53719c5dd14d2

Now you should compare your downloaded ISOs with the md5sum given on the page you downloaded the ISOs from. If they differ, your ISOs are wrong, if they are the same, the failure is on another part.

i downloaded 2 isos from 2 different mirrors
they were the same when i checked the md5sums

i added the missing package into the 3rd iso and re-burned and the install completed without error
so i assumed this was an error of the person who put togther the isos and sent them to the mirrors

as far as i can see, my install is working just fine

Bet it is. Some ISOs are released with last-minutes changes and can be buggy.

The principal thing is to get a minimal working system and later you can get the rest of the stuff from the URPMI mirrors.