Dan 12:4 "the true knowledge" - they could take out the word "true."
It doesn't belong. Yet, when they cite the verse, that is the word that is emphasized.
Eph 4:8 "gifts in men" - should be 'gifts to men (as in humans or people, not males). Verse 7 contradicts "gifts in men."
1Thes 5:3 "Whenever it is that they are saying ..." - should be "while they are saying ..."
And they should have a footnote that says "'are saying' is not the same as 'the cry of.' Cmp 'are saying' in Matthew 16:13.'"
Mt 10:15; 11:22, 24; 12:36 "Judgment Day" - should read "day of judgment."
This is the exact same expression used in 2Pet 2:9 and 3:7 rendered "day of judgment." They even have a talk that tries to make a difference between the two expressions, but never mention that in the Greek they are exactly the same.
Here is a curious note: In the 'Bible Teach' book there is an appendix chapter on what is Judgment Day. But it never quotes or cites the four verses in Matthew where the term "Judgment Day" is used. (These are the only four places in the NWT that the phrase is used.)
Mt 19:11 "have the gift" - should read " "to whom it has been given."
And take out the nonsensical header "gift of singleness" The Bible never says singleness (or marriage for that matter) is a gift. The ability to live successfully with singleness, and having a good mate are gifts. (Imagine buying a light switch at Lowe's and the salesman says; 'And we are throwing in two free gifts with that switch, ON and OFF.')
Lu 6:38 "... people will give ... They will pour ... they will measure ..." - The Greek uses neuter pronouns usually indicating God will repay.
The NWT changes them to refer to people doing the repaying. (Although, God may use people for this purpose.) This isn't a big one. Just a pet peeve of mine.
Jn 1:1 "a god" - This is, admittedly, a literal translation. So no argument on that.
But ... "a god" contradicts the context of the epilogue (Verses 1 - 18). "A [something]" in English usually means 'one of a class.' Thus, 'a car' is one of the car class, one example of many. But the "Word" is "an only begotten son from a father," "the only begotten god." (Vss. 14, 18) He definitely is not 'one example of many.'
How to translate it so that it fits the context? My take: "the Word was God[like]." (I hope I don't start a big argument on this.)
I could come up with more in time (esp. in Revelation). But, having said these, in fairness, I like certain general features of the NWT. It can be very useful when used in conjuntion with another or several translations. Just watch out for the mines.