Luke 18 opens with a parable, and while I have already said that parables are weird, and this one's no exception, I think Jesus explains it pretty plainly. The idea is that if even a judge who seems to care about little can be persuaded to seek justice, then how much more can we depend on God to seek justice?
In verse 17, the SAB asks, Is it good to be childish? I've answered this before, but I'll give a brief response here anyway: While there are some aspects of childishness that are not desirable, the particular childish trait of humility is what Jesus is looking for in this example.
Then comes a story starting in verse 18 that brings up a number of questions. The man in this story is asking Jesus how he can be saved, and Jesus gives him a number of odd responses. First of all, there's "Why callest thou me good? none is good, save one, that is, God." Is Jesus saying that he's not good, nor is he God? No, I think it's understood by most that Jesus is pointing out a belief held by the Pharisees (that only God is good) and warning that since the Pharisees don't accept that Jesus is God, his question, as worded, could be tantamount to blasphemy. Next, Jesus goes to "Thou knowest the commandments," and tosses out a few. I think it is telling that Jesus mentions none of the commandments that mention God, and that's thematic. When Jesus goes on to tell the man to give everything he has to the poor, and the man is sad to hear this, it shows that this man's true god was money. When Jesus goes on to tell his disciples that it's hard for a rich person to go to heaven, I think that is still the point being made: that for a lot of people who are rich, money is their god. I don't think this means that no rich person can ever go to heaven, only that people need to keep money in proper perspective.
While I don't think verse 27 is making the claim that God can do anything, Can God do anything? is a fair question to ask. Of the three verses in the No column, the first two are really a matter of faith: since these people didn't have faith that God/Jesus could do those things for them, he wasn't able to work with them, but it was their failing, not God's. The third item is a more interesting one, because yes, it is believed that God is incapable of lying. The thing to note about this is that it's not like God doesn't have the ability to lie, but rather that it's against his very nature to do so. So you could take that either way.
In verses 29-30, I don't think that Jesus is asking people to abandon their families, but he's pointing out that some people will lose many things that they hold dear because they chose to follow Jesus, and he assures them that they will receive a greater reward in the end.
Did Jesus forewarn the apostles of his death and resurrection? Yes, he did, and repeatedly, but as the verse in John's gospel points out, they didn't understand it.
The SAB asks of the last story in this chapter How many blind men were healed near Jericho? and When was the blind man (or men) healed? Well, each telling of this story is different enough that it seems to me that it could be actually two or three different events with some similarity. I mean, note also that Jesus touches their eyes in Matthew's gospel, but in the other two he just talks to them. Why does Mark know the name of the blind man, but the others do not? It's possible these are contradictions, but it's also possible that these are completely different stories.