Asalamu Alykum Yahya
Regarding your question
The Quran is indeed protected by God Himself.
15:9 Lo! We, even We, reveal the Reminder, and lo! We verily are its Guardian.Now lets assume that people were to try to change and tamper the words of the Quran and spread it through the world, this does not mean that God did not fulfill His promise and the verse has become disproven in anyway.
When God says that He will remain to be the protector of the Quran, it does not mean that there will not be any human errors in the transmission of the Quran or that some ill people will not try to corrupt it, as there might always be the cases like that.
It is more logical for a reader of the Quran to take the majority read version of a Book especially in light of the verse 15:9. One wonders that when God is telling you He is its guardian, He is most likely going to make it rule over all other versions that have errors or have been tampered with. The article and debate that brother Duster shares shows that the differences between the version is not a close margin. Its a 95% to 5%.
If it was a 55/45 or 60/40 then one might question the case.
God has chosen to protect His message in two ways by a written manuscript and a oral version.
We have evidence that the majority reading of the Quran that is available today in our hands has been the same reading throughout history and we do not note any changes or tampering to it.
Also brother Yahya I also would like to respectfully ask you to just take it easy just a little bit and start reading more and more on this website before you ask one line questions followed by another.
It is hard for anyone to answer questions by the way your asking them, despite most of them if not all of them have already been somewhat answered on this forum somewhere.
Please make use of this link below. What ever verse your interested in questioning just type it in the "search" area and a lot will come up. Just browse through the posts and Insha'Allah you will find lots of information or discussions about them.
Jazak'Allah
Salam
Search
http://quransmessage.com/articles/search%20FM2.htm