[andrewas]

Yes, when you start SoU select 'use premade character' and select your characer from the list. However, you will find the SoU is balanced for a character starting at level 1. It will scale to a higher level character, but not very well and only to a limited extent.

HotU is designed for you to bring an SoU character in, but it works fairly well with a NWN character as well, so it would perhaps be better to take your NWN character there instead.