Oh ye Tempter...

I had a very similar experience as Usetawaz described above. When i didn't "get" the message that way, i then had a dream telling me that ACIM was leading me off my core spiritual path, and i knew when i woke up that i should drop it and so i did.
There was also a synchronicity of sorts with a spiritual friend of mine who around that time started talking about the clear and repeating messages from his guidance telling him he should drop it as well.
There is truth in ACIM, but it's partial or half truths, and you know what they say about those, that they are worse than whole lies for they can deceive even the Soul. I found that despite it's talk of Love, Oneness, Spirit and God, that it actually programmed negativity and "ego" into my mind.
How it does this is actually quite simple, it's written in a very repetitive, looping manner which after awhile of reading "bores" or lulls the conscious mind to the passive state, allowing the subconscious or ruling mind to open up more.
It then implants repeatedly a veiled suggestion into the subconscious which is based on polarization and "ego", the same things it purports to help us get rid of! It talks far too much about ego, fear, etc. and in such a polarized manner with Spirit, Love, etc.
The subconscious mind is a sponge that responds to positive direction. You tell it a thing is so, and it is so. You tell it, "you are hot" and you become hot. It doesn't compute "nots, no's, don'ts," and various other negatives. Telling it you are NOT hot, well it doesn't hear the "not" part.
So, when it talks so much of ego, fear, separation when you are in that vulnerable, subconsciously receptive state, guess what get's programmed? The things you don't want!
Hence, it is as a wolf in sheep's clothing, and very deliberately designed this way by lacking in Light forces to mislead and keep humans stuck in the very problems and issues we are trying to grow out of.
So what do i think of ACIM--i think it's harmful in essence, and instead of donating mine i threw it away.
I have a real time relationship with the purported Teacher of same, why would i make a book, a course my teacher, when i have the Fluid, Real deal in my life? Living and breathing guidance v.s. a rigid, structure of a book?
I tell you this much, it did not come from my Teacher.
But i don't ask that others take my word for this, i sincerely hope that others so interested will deliberately hook up to the most spiritually expanded Guidance there is, via both that specific intention/prayer/request/affirmation and through opening self up to the remembrance and feeling of Love and/or gratitude, and ask these expanded Sources what is the real deal on ACIM.
Speaking of the Teacher, he was very clear in some of his warnings to future generations that others would arise that would claim they were or of the Christ, but to not listen to these. He said *even some of the very "elect" will become fooled in those days*.
I got hoodwinked for awhile, but it was a good learning experience and helped open up my eyes to the ways and methods of the lacking in Light forces. It was a catalyst for me to become more aware of these in general, and now it is easier for me to spot other wolves in sheep's clothing. Now i apply discernment and discrimination to all outer so called "spiritual" works and sources--especially the popular ones.