I have Vista Home Premium on my computer. I upgraded from XP and when playing Morrowind it's O.K. but can't get Construction Set to work properly! Tried looking thru forums to find solution for this problem but probably not looking in the right place. Can anyone give me some help on this? It 's mostly that I can't get the keys to work. Put Morrowind in its own folder and Oblivion in Bethesda's and can't even use Oblivion Tes IV Construction Set for the reason TES III took it over. Everything on computer is the same --- CPU, NVidia 8500 GT, has more memory, the only other thing that's changed is upgrading to STUPID VISTA!!! If I go back to XP Oblivion won't work!!!!!!

Try installing Morrowind outside the regular folders.(CS follows morrowind.) It probably doesn't know how to handle permissions.
So instead of C:\Program Files\Bethesda Softworks\Morrowind. Do something like C:\Games or any other new folder.
(and not inside the user-folders!)

Did that still doesn't work. Thanks for your help though. WELL looks like I might have to dual OS thanks to MICROSOFT!!

There are two different types of CS. The one from morrowind is placed outside of the morrowind folder and gets his own inside the bethesda folder. The CS-IV gets installed in the oblivion folder itself. Both don't conflict with each other, there is only the possibility of confusion. Take a look at Help->About if you're unsure which one you're using. Could you elaborate what isn't exactly working the first place?