Enabled: Enables IntellFade mixing and the ACI chunk to be used for handling items in the decks (item silence/low-level sound is trimmed, mix and fade points are applied, etc.). This is the default setting. Inversely, when this is disabled, the items will still mix with AutoDJ, however, the silence will be present at the beginning and end of the item as in the original raw underlying source and mixing will normally include gaps of silence depending on the raw audio (this can be useful for purposes where tight mixing may not always be desired - e.g. Classical or Karaoke).
Karaoke Items: Ignore Intro and Ignore Outro options disable IntelliFade mixing, as discussed partly above, but specifically for items marked as Karaoke in the ACI chunk (.k) only. This allows having IntelliFade mixing enabled for all items (keep that option ticked), except for Karaoke files, and allows you to limit the exception to either the Intro or Outro, both or none.