Nero vision express2

hi all,
I installed nero 6 ultra edition the latest verion (package 1) and it works fine and i allso installed nero vision express2 (package 2) latest version and i paid for the s/n key. my problem is when i installed nero vision express i got a error that said DVDUI.DLL, EXPRESSUI.DLL, VCDUI.DLL could not be registerd and i dont know why? in package 2 there was 3 programs vision express, (recode and showtime) and these 2 work fine but not nero vision express. i have reinstalled several times too. any help would be appreciated

XP Home
2.4 pentium
512 ddr ram
80 gig hd
up to date on sevice packs