A common pet peeve among Mormons is when someone assumes the Book of Mormon is the Mormon version of the Bible. Fuck's sake, people, "we believe the Bible to be the word of God" (Article of Faith 1:8)! We just have another book of scripture to help straighten things out. See, it's like a pair of glasses - one corrective lens isn't going to be enough to get your vision into focus...
So if Mormons are cool with the extra books found in The Book of Mormon how do Mormons feel about the Apocrypha? Well, quite frankly, Mormons never touch it. Here's what God told Joseph Smith:
"Verily, thus saith the Lord unto you concerning the Apocrypha—There are many things contained therein that are true, and it is mostly translated correctly; There are many things contained therein that are not true, which are interpolations by the hands of men. Verily, I say unto you, that it is not needful that the Apocrypha should be translated. Therefore, whoso readeth it, let him understand, for the Spirit manifesteth truth" (D&C 91:1-4).
In other words, there's too much shit to wade through; don't waste your time. Oh, and don't read the Songs of Solomon either - they're not inspired. Those Old Testament apocrypha are the worst! (But the Book of Judith seems to have inspired the Book of Mormon somehow.) But the New Testament apocryphal gospels are a little trickier. Some of those darn Gnostic gospels actually predate the gospels included in the final cut. It seems as though their exclusion from the Greatest Hits compilation was more a matter of politics than unbiased research.
What if, in addition to pseudopigrypha, there were a huge absence of authentic and essential texts in the Bible? Why aren't the LDS Church and Mormons at large more interested and involved in a revision of the canonical Bible texts? Does corrective power of The Book of Mormon really justify having the wrong prescription in the other lens?