First off, let me say: I think almost every philosopher's works are difficult to understand or get through. They operate on such a logical level, that it's almost like reading a textbook on some high-level mathematical concept. Sometimes, I'll read a work, and then have to go on the internet to find a summarized version just to find out what I just read, lol!
Yes
As I mentioned before: I think moral truths are easy to apply in the general case; it's in the specific situations that I'm more hesitant to agree with them.
For example, number 1 sounds like a great rule to follow. It's basically a rephrasing of the Golden Rule: "Do unto others as you would have done unto you." I try to base my actions around this principle, but I feel it's easy for me because I'm not in any stressful or highly intense situations that push me to do otherwise. Most people I meet are nice to me, so it's not too much for me to do the same, but let's consider a special case...
Now, I think stealing is generally wrong. You're taking the honest living of another man for your own benefit. However, what if you were a victim of a financial "perfect storm"? You were a hard-working, honest man who considered the welfare of others, but now you suddenly find your entire family living on the street. Let's also say that much of your misfortune was the result of a powerful and wealthy, yet evil, man's machinations. Your family, including your two infant children, are dying right in front of your eyes. One day, you suddenly find yourself in a situation where you can swipe a bit of food from the evil man's kitchen. Doing so will have no effect on the evil man, since he's rich, and he probably won't even know you did it or that anything was stolen from him. If you live according to Rule 1, you don't, because you don't believe in stealing, and you wouldn't want anyone stealing from you. Instead, you simply return to your family and watch them die.
If I heard this story, and was asked what the poor man should do... I'd say "Go steal from that bastard." I think there are a few out there who would agree with me. Is the stealing justified? No, of course not. The man is still committing a wrongful act (if you consider stealing wrongful, which I hope you do

); however, is it a greater wrong to steal or to let someone die? Though the answer to this question may seem obvious to some, other comparisons can be made where it would be a much harder call. In the situation I described, though, I think many of us would probably be lenient on the poor man, given the circumstances.
I think Kant would argue that his principle isn't like the golden rule because he thinks wants and actions have nothing to do with morality, the consequences of an action don't matter only as long as they were done because it was the right thing to. So if you are treating others the way you want to be treated, your doing things out of self interest and Kant would say that is immoral, that being said I don't necessarily like Kant
But the example you gave, it could be considered moral to take the food and still be applicable to Kant's first truth, it all depends how you form the maxim. You assumed the maxim was "stealing" and since if everyone stole the world couldn't exist, therefore it's immoral to take the food, but what if you made the maxim "stealing food from the extremely wealthy to save your starving children"? Then you could imagine a world where the individuals with starving children stole food from the extremely wealthy who don't even notice, that world is plausible, and no worse then the current world therefore stealing the food IS moral...So Kant made this rule extremely flexible, and I can't think of any situations where it wouldn't work still...
Ok but, simply put, when one group with one set of laws is judged against another group with another set of laws on the same issue, which set of laws is correct? And maybe it is because there are no universal moral truths that people are able to stand up and say something is wrong.
Wait....What? Wouldn't there have to be a standard for them to say something is wrong?
Aside from morals, if everyone thought it a universal truth that our solar system is our universe, would this really be that healthy? They may be right, but holding onto this perceived universal truth is preventing them from seeing a different alternative.
In order to be a universal truth it would have to be true, so those people would be wrong. Now the danger lies in assuming something we know already to be absolutely true, if we classify something as an absolute truth and we are wrong, then it's not really a truth at all now is it...So that makes the process of finding moral truths that much harder, even if you think you have it, is there really any time when you can ever say, yes it is absolutely true and end all further development towards that idea? What if your wrong?
Now if there are no universal moral truths, this does not mean that a species can’t come together and generally agree on certain principles. A species may still ultimately realize that there are no universal truths in their moral or legal system, but for whatever reason, have found a stable path. A path that has been forged by the environment they inhabit – a different environment would forge a different path. Morals come together, evolve and work, just in the same way that matter comes together, evolves and works. And this only happens in the right combinations or circumstances.
This may be the case, and this may be exactly how modern laws were formed, they evolved over the years. BUT in order for a society to exist, they have to hold some common moral values in order for society to actually exist, now is that to say that these common values that are required for society to exist universal? Maybe... For example murder must be disapproved of, if it weren't then individuals wouldn't risk living together in large groups, they would be solitary, maybe forming small groups they could trust to not kill them at best, but nothing that would allow for a society to exist, so all societies must disapprove of murder. So regardless of the environment that must be true for all, right?
So it seems we do sort of agree. But i feel a common moral truth is the result of process and conditions, and i hesitate to use the word universal because we now recognise the possibility of many or an infinite number of universes, each potentially with it’s own set of cosmological laws. So perhaps you would like to use the word multiversal moral truth? I don’t think you would be so confident with this idea though.
Now that's a tough one
If the same principles of nature, such as evolution and physics applied to every other universe then I could probably argue that it wouldn't make a difference which universe you were in, life and societies would exist in such a similar manner that there would still be truths that apply to all of us... But if different laws of physics and biology are found in other universes...Then hell, it's anyones guess as to what the heck would happen, I don't think we can comprehend those implications at least I can't at the moment
Of course the idea of eternal morals is a human concept, we would be in a better position to debate this if we were in contact with intelligent cultures from other planets. Do they have morals? If so, what kind? And so on. Our morals may be similar, or they may be completely different.
You don't know if eternal moral truths are a human concept, maybe on planet Gorbalax they are sitting discussing the same exact thing
Perhaps what we can say is that the framework for morality is there in the universe. In the same way that the framework for stars and planets. But the question is why is it this way, and why does it seem so right? It seems so right that we cannot comprehend other (theoretical) universes having a better system. Ours is just the best and only way we know. At this point my head explodes

because i am physically unable to comprehend a different reality to our own 3 dimensional one.
*tapes indigo's head back together*
Well what if we consider cultural relativism and instead call it universal cultural relativism, and instead of comparing societies on Earth, we compare two different universes and their views, wouldn't we come to the same conclusion that cultural relativism did?