issue in migrating old niosII designs into QuartusII 9.0

first of all, if you have custom components that are included in your sopc design, then you will need to get the sopc builder working and generating this design before you continue to compile with quartus ...

normaly it is almost no problem to upgrade from 7.2 to a newer version, well almost ...

if your custom component is stored inside your project working folder then the sopc builder should find it automatically.

if your custom component is stored anywhere else, you must add it via sopc builder -> tools -> options -> IP Search path as you already said. but then you could either close the sopc builder and reopen it or Menue File -> Refresh System

with both methods your custom component must apear inside the system contents component library tree