Sola Fide!

At first glance, your criticisms seem plausible; but they don’t withstand scrutiny.

(1) Christ’s Birth: The passage from Alma 7:10 is always tweaked in order to demonstrate a contradiction. It says Jesus would be born “at” rather than “in” Jerusalem. It also qualifies that as the “land of Jerusalem.” The word “at” is less specific than “in” and conveys a less specific connotation as in “near” or “by” or “in the direction of.” From the perspective of Mesoamerica, Jesus was born near, by and in the relative direction of Jerusalem. If you think “at” is enough of a contradiction, you might ask why people feel the need to always change it to “in” rather than using the actual text. I have spoken with others who insisted that “at” Jerusalem must mean “in Jerusalem” yet they’re not quite as rigid when I remind them that Peter sat and warmed himself “at” the fire. http://www.biblegateway.com/passage/?search=Mark%2014:54&version=9

(2) Origin of term “Christian:”You think that the people of Antioch really spoke English? Of course, that’s rhetorical; the people of Antioch still speak Aramaic even today. Their term that we translate “Christian” is merely Luke’s Greek translation of their word and ours is a transliteration of the Luke’s Greek word Χριστιανούς. I would surmise that if the people of the Book of Mormon believed in Christ, they would have called Him some equivalent term like “Messiah” and His followers would have been called something like “Messiahites.” However, a good translator would recognize the modern equivalent as being “Christian.” This could really only be a legitimate complaint if ancient Americans spoke English back in 73 B.C. Do you think that’s likely?

(3) Length of darkness at the Crucifixion: If you will read verses 20 and 28 of the passage you cite from Helaman, you will see that the darkness reported in the book of Mormon is localized from their perspective. “there shall be no light upon the face of this land.”
… “and these signs and wonders should come to pass upon all the face of this land.”

(4) Corporeal nature of God: You realize that the logic you employ doesn’t even need to be revised to demonstrate the Jesus is not God? If God is spirit and Christ pointed out that His body of flesh and bones indicated He was not a spirit….” Now, I wouldn’t take that approach because I believe that Jesus Christ is God, but surely you see the problem of the passages you’ve put together? I’m new to this kind of forum and I don’t know how extensive of a reply is appropriate, but I assume brevity is the standard. Much can be said in defense of this LDS concept, but an adequate response would probably be too lengthy here.

(5) Rest assured that Mormonism does not countenance the idea that man can obtain salvation by his own doing. Even if understood as you suggest, the passage from 2 Ne. 25:23 says that it is still by grace that we are saved. The Book of Mormon points out that “all we can do” is repent. http://scriptures.lds.org/alma/24/11#11

http://scriptures.lds.org/mos/2/21-25#25 points out that nothing you do can earn you anything with regard to salvation. However, God requires obedience. Even you stipulate the necessity of baptism. I have Calvinist friends who would call that works based salvation. Hebrews 5:9 demonstrates that it is obedient believers who shall be saved.

Allred has written numerous articles on Mormonism, including a 38-page review against
Norman L. Geisler’s “Scripture”, in The Counterfeit Gospel of Mormonism (9–49. Eugene, Ore.: Harvest House, 1998)

Geisler is a Calvinist scholar profiled on Wikipedia

What is said of Mormonism below is secondhand research, but I will link as much to KJV and Mormon scriptures as I can so that people can check it out for themselves.

Material for this section comes from: The Interactive Bible.

Christ’s Birth
KJV: Born in Bethlehem - Matthew 2:1
MS: Prophesied to be born in Jerusalem - Book of Mormon, Alma 7:10.

Origin of the term “Christians”
KJV: After Christ’s death and resurrection, at Antioch - Acts 11:26
MS: Nephites are named Christians 73-72 BC - Book of Mormon, Alma 46:13-16, verify date in notes at the top.

Length of darkness at the Crucifixion
KJV: Three hours - Luke 23:44
MS: Three days - Book of Mormon, Helaman 14:20-27, esp. 27.

Spiritual vs. corporeal nature of God the Father
KJV: God is spirit - John 4:23-24. Christ says a spirit does not have flesh and bone - Luke 24:39
MS: The Father has a body of flesh as tangible as man’s - Doctrines & Covenants, 130:22

The nature of these inconsistencies seems cut and dry, unless the Mormon scriptures have been abrogated by something later.

I do wish to bring up something, because this discussion has been informative. Looking at The Articles of Faith for The Church of Jesus Christ of Latter-day Saints, point 3:

We believe that through the Atonement of Christ, all mankind may be saved, by obedience to the laws and ordinances of the Gospel. (emphasis mine)

This is corroborated by the Book of Mormon, Second Nephi 25:23:

For we labor diligently to write, to persuade our children, and also our brethren, to believe in Christ, and to be reconciled to God; for we know that it is by grace that we are saved, after all we can do.

This is in contradiction to Ephesians 2:8-9 (continuing with KJV):

For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast.

Biblical scripture does not leave the door open for a man to obtain salvation by his own doing. Man is corrupt; all of our deeds are like filthy rags (Isaiah 64:6). There is the Gospel, not of laws and ordinances, but of good news. Jesus Christ, the Son of God, was born incarnate, was crucified, died, and rose again, like the Scriptures said He would, as payment for the sins of the whole world. Those who believe and are baptized in the name of the Father, Son, and Holy Spirit shall be saved.

Science may be used to expose religious quackery and scams as you noted in the news report about the Mormons.

Science may change, but more likely it be understood and practiced better in order to obtain more knowledge. Copernicus thought the orbits of planets around the sun were circles because circles are perfect and God would have made perfect orbits.