First time, I would say, go by the book and use OO.
On my fifth flush, I use Coconut Oil in the morning. ( In the night I still used OO). It was a very productive flush. Now, since every flush is different, I dont know if it was just time to have a productive flush, OR coconut Oil did the trick.
Needless to say, CO was a lot more palatable than OO. I drank nearly 1/2 cup CO follwed immediately by Grapefruit Juice. Had no problems.
Next flush I am planning to do 1 full cup of CO. No more OO. Lets see if I get good results.
Ppl have flushed with Almond Oil, Walnut Oil, Sunflower Oil, Pumpkin Seed Oil. The Oil should be cold pressed/ Organic/ Not refined/ Not hydrogenated. Try another oil and post the results. A lot of ppl are getting sick of OO (Olive-Oil) and looking for alternatives.
The important thing is any Oil should work. I dont understand why there is so much stress on OO (Olive-Oil) in all the books.