Brett, the new releases, and hopefully ones in the future, are made not to overwrite users.ini when you extract it into your old ULib folders.
This way, the person installing it won't have to do any moving/renaming of thier users files on thier own.
If someone runs it without the users.ini, I believe it creates it with a generic, or asks the admin to with an error/note.
As for the missing files, ULib should be extracted to gmod9/
Not gmod9/lua , as it has a materials folder now.
From the ULib readme
To install ULib, simply extract the files from the archive to you gmod9 folder.
When you've done this, you should have a file structure like this--
<gmod9>/lua/ULib/init.lua
<gmod9>/lua/ULib/misc.lua
<gmod9>/materials/ULib/menu.vtf
That should fix any missing textures, etc.