After just creating another Drupal 6 website that uses ImageCache, ImageAPI, ImageToolkit, CCK, and ImageField, I thought I'd make some notes here about the problems I ran into when trying to use ImageField with CCK to let users upload images to my website. I encountered several very frustrating errors along the way, and here are my notes related to those errors.
Note: This blog post is about Drupal 6. Things have changed quite a bit in Drupal 7, and these tips are not likely to be helpful there.