what about moses using JHWH, he would have put vowel markers as was done with hebrew language (which didn't use vowels as we do) and as time went on they were allowed to be lost and finally we get the LORD change, was it jews or christians that changed JHWH for LORD?
Vowel markers (niqqud) did not exist when the OT was written and so they have nothing to do with the substitution of YHWH with other divine titles. The main reason was the rise of true monotheism in the post-exilic period which stressed the uniqueness and singularity of God (as opposed to all the other gods who have their own names, cf. Philo of Alexandria, Vita Mosis 1.75), Yahweh was a vestige of Judah's henotheistic past. So in Jewish writings from the third century BC onward, you find writers preferring to refer to God as "Most High" or "God" or "Lord" or even the "Name" rather than using the name Yahweh (cf. the Aramaic apocalypse of Daniel, Sirach, Wisdom, 1 Maccabees, etc.). This was especially the case since there were still polytheistic and henotheistic Jews and Samaritans who used Yahweh as the name of one of the gods they worshipped, cf. the Amherst Papyrus (third century BC) where Yahweh is worshipped alongside Horus, Baal, El, Mar, and other gods. Yahweh was also used (in the form Iao) in magical spells alongside other pagan names of gods (cf. the PGM corpus of ancient magical spells).
The second reason is that the Bible itself condemned the use of the name, at least in the LXX and possibly its Hebrew Vorlage. If the Law of Moses explicitly says that you are worthy of death by stoning by merely uttering the name, then of course people who considered themselves faithful to the Law would not utter it. So it was not a mere "superstitution" as the Society puts it, it was actually done to obey a commandment of the Hebrew Bible. In addition to the ban on pronouncing the name in Leviticus 24:16 LXX, the word of the Lord in Jeremiah 44:26-27 LXX also cursed any Jew living in Egypt who happened to utter the name: "Thus hear the word of the Lord, all of Judah who dwell in the land of Egypt: Behold, I have sworn by my great name, says the Lord, that my name shall no longer be named in the mouth of anyone from Judah in all the land of Egypt, if anyone says that the Lord God lives, because behold, I will be watchful against them and inflict harm on them". Since the LXX was produced in the third century BC in Egypt for use by the Egyptian Jewish community (who would have read the Bible aloud in those days), the translators took this seriously and substituted kurios wherever YHWH appeared in the Hebrew text. The incursion of YHWH in the text of the LXX is a later development, as the earliest attestations of the LXX text contain kurios (compare also 1QIsa which in Isaiah 3:7 replaces YHWH with 'dny "Lord") So the change already occurred centuries before Jesus, but it was done principally to obey a rather explicit commandment in the Bible. The Community Rule of the Qumran community thus has as a rule: "Whoever pronounces the name that is honored above all, whether by blaspheming or by accident or for any other reason, whether while reading a book or while blessing, shall be excluded and will never return to the community" (1QS 6:27-7:2). That was written in the first century BC.
And what do you think of how other Christian faiths happily use OT Scriptures obviously talking about Jehovah but use the LORD as if they are talking about Jesus? isn't this as incorrect as what you point out above in regards to NT,
That is exactly what you find in the NT: Paul and other writers quoting scriptures that were "obviously talking about Jehovah" but applying them to Jesus. The use of such scriptures in Christianity has a long exegetical tradition reaching back to the NT itself.
Surely if we are going to be strict with the NT making sure the correct Lord is applied to the Correct LORD we should do the same with OT too?
I would certainly prefer the use of YHWH in the OT although it is worth noting that the practice of rendering the name as "LORD" is a continuation of the similar rendering in the LXX (and later the Vulgate) that Bible authors themselves used in the NT, so the two cases are not quite the same. They are also very different in another way: Bibles that render YHWH in the OT as "LORD" do so consistently, clearly (LORD always being in capitals to distinguish between instances of the Hebrew word for "Lord"), and often there is a note or preface that explains that "LORD" in capitals renders the tetragrammaton. The NWT, on the other hand, interpolates "Jehovah" into the NT arbitrarily, without regard to context, and without any textual basis.