There is no answer because you're looking in the wrong places. The Bible does not contain a commentary on itself, thus we have theology courses that examine the scriptures in light of their historical settings. (As opposed to the JWs, who tend to view the scriptures in the context of their own world view.)
For example, looking at your first example regarding the curse of Noah:
Bergsma and Hahn...argue that maternal incest makes the most sense given the limited evidence. For one, Lev. 18:7-8, which is cited to support paternal incest, equates “father’s nakedness” with the intercourse with the father’s wife:
7 The nakedness of thy father, or the nakedness of thy mother, shalt thou not uncover: she is thy mother; thou shalt not uncover her nakedness.
8 The nakedness of thy father’s wife shalt thou not uncover: it is thy father’s nakedness. (the NRSV is even more explicit, translating v. 7 as “You shall not uncover the nakedness of your father, which is the nakedness of your mother”; see also Lev. 18:14, 16; 20:11, 20, 21, for other references to a man’s nakedness meaning his wife’s nakedness)Maternal incest was so vilified in the ancient world because it threatened the patriarchal structure of a family or clan, which would suggest that Ham was attempting to usurp power in his family. It would explain why the text mentions Ham telling his brothers what he had done. There are several examples of sons seeking to replace their fathers by claiming their wife or wives in the Bible and in the ancient Near East (but there are no examples of paternal incest as a means to seize power). Bergsma and Hahn also offer other smaller pieces of evidence for their argument, but this is the crux.
Perhaps the most interesting part of their theory is that it explains why Noah cursed Canaan and not Ham. If Canaan was the offspring, not of Ham’s own wife, but of his father’s wife, that would explain Noah’s wrath. It would also suggest a possible explanation for the specific references in vv. 18 and 22, which both specifically note that Ham is the father of Canaan, while neglecting to mention Ham’s other children or the offspring of Japheth or Shem. Perhaps the author of Gen. 9 is seeking not only to explain the origins of the curse on Canaan, but also how Canaan came to be in the first place.
2) “‘Anyone who curses their father or mother is to be put to death,” God told Moses. (Leviticus 20:1, 9) Then why Jesus was crucified instead of Satan who presented God as a liar to Adam and Eve. Why? No answer.
Actually, this one is answered in scripture. Jesus was unjustly put to death by the Jews, which placed them under condemnation and caused them to be dispersed to the heathen nations by the Romans. (See Ezekiel 39:23-24, 26) Satan has already been judged and condemned by God, and at the conclusion of the Millennium will be cast into Outer Darkness with those who followed him. And Jesus already has been exalted and sits on the right hand of the Father. The scriptures also are clear that Jesus came into the world to take upon himself, willingly, the sins of the world and to be unjustly slain, thereby being mandkind's Savior and Redeemer.
3) To the important question ‘Does the human spirit rises upward and the spirit of the animal go down into the earth?’ Bible itself answers “Who knows?” (Ecclesiastes 3:21)
The book of Ecclesiastes was said to be written by Solomon, who was a king, not a prophet. And his book is a philosophical work, not an eschatological one. Solomon married heathen women who led him to sin against the God of Israel and to erect heathen altars. And Ecclesiastes was written in his final days, when he was a bitter old man. Unfortunately, the Adventists used his writings to attempt to show that man does not have a spirit that survives death. But the early Christians clearly believed that man has an immortal spirit. Jesus, when he was crucified, went and preached to those who were dead. Peter writes:
For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but [made alive] by the Spirit: by which also he went and preached unto the spirits in prison; which sometime were disobedient, when once the longsuffering of God waited in the days of Noah, while the ark was a preparing, wherein few, that is, eight souls were saved by water. (1 Peter 3:18-20)
...Who shall give account to him that is ready to judge the quick and the dead. For for this cause was the gospel preached also to them that are dead, that they might be judged according to men in the flesh, but live according to God in the spirit. (1 Peter 4:5-6)
How could Jesus preach to the dead -- the spirits in prison -- if they ceased to exist? That's why Jesus told the malefactor, “Verily I say into you, this day shalt thou be with me in Paradise.” The Adventists say the comma was misplaced, and that he was saying, “I'm telling you today, you will be with me in Paradise.” But nowhere else in the Bible, or in any other ancient document from any culture, have they shown that that idiom was ever used. Jesus certainly never used it, nor any of the prophets for that matter. “I'm telling you today” was not a recognized figure of speech.
The Bible never specifically says animals have spirits. Catholics say no. Most Protestants say yes. If spirits animate the flesh in man, why not animals? They live like people and are subject to death like people. Their bodies appear bereft of life when they die, so why not? That the Bible is silent on the issue means nothing. The Bible is silent on many things, but seeing how God put the proper care for animals into the law, to me, is significant.