Not reading the whole thread, so if this has been said, please move on.
First, you are pulling out of context what is in the actual verse! Forget that Paul is clearly talking about everyone sinning since sin entered the world, through Adam.
"Therefore, just as sin entered the world through one man, and death through sin,and in this way death came to all people, because all sinned—To be sure, sin was in the world before the law was given, but sin is not charged against anyone’s account where there is no law.14 Nevertheless, death reigned from the time of Adam to the time of Moses, even over those who did not sin by breaking a command, as did Adam, who is a pattern of the one to come." Romans 5:12-14
You should stop using the KJV, since you do not understand it. The KJV clearly states the truth, but the words it uses are not common, and therefore, you have ignored them. Here is the single verse in NET.
"Yet death reigned from Adam until Moses even over those who did not sin in the same way that Adam (who is a type of the coming one) transgressed." Romans 5:14 NET
You missed the part in KJV, where it clearly says, "after the similitude" of Adam's transgression.
"Nevertheless death reigned from Adam to Moses, even over them that had not sinned after the similitude of Adam's transgression, who is the figure of him that was to come.' Romans 5:14 KJV
"After the similitude" in other versions is:
"Nevertheless, death reigned from the time of Adam to the time of Moses, even over those who did not sin by breaking a command, as did Adam, who is a pattern of the one to come." NIV
"Yet death reigned from Adam to Moses, even over those whose sinning was not like the transgression of Adam, who was a type of the one who was to come." ESV
"Nevertheless, death reigned from Adam to Moses, even over those who did not sin in the likeness of Adam’s transgression. He is a prototypeof the Coming One."HCSB
In other words, people DID SIN! But they did not sin by eating the fruit in the garden that was forbidden, but by sinning in other ways. Here is the Greek:
"12 Διὰ τοῦτο ὥσπερ δι’ ἑνὸς ἀνθρώπου ἡ ἁμαρτία εἰς τὸν κόσμον εἰσῆλθεν καὶ διὰ τῆς ἁμαρτίας ὁ θάνατος, καὶ οὕτως εἰς πάντας ἀνθρώπους ὁ θάνατος διῆλθεν ἐφ’ ᾧ πάντες ἥμαρτον—13 ἄχρι γὰρ νόμου ἁμαρτία ἦν ἐν κόσμῳ, ἁμαρτία δὲ οὐκ ἐλλογεῖται μὴ ὄντος νόμου,14 ἀλλὰ ἐβασίλευσεν ὁ θάνατος ἀπὸ Ἀδὰμ μέχρι Μωϋσέως καὶ ἐπὶ τοὺς μὴ ἁμαρτήσαντας ἐπὶ τῷ ὁμοιώματι τῆς παραβάσεως Ἀδάμ, ὅς ἐστιν τύπος τοῦ μέλλοντος." Romans 5:12-14 Greek
πάντες ἥμαρτον - this means ALL SINNED
Paul continues in verse 13a
ἄχρι γὰρ νόμου ἁμαρτία ἦν ἐν κόσμῳ, "for before the law was given, sin was in the world."
The grammatical pattern, which is similar to what Paul uses in 2 Corinthians, in refuting error.
1. Paul justifies his statement at the end of 5:12 that "all have sinned [in the course of history]" by pointing out that "before the [Mosaic] law was given, sin was in the world."
2. An objection that he knows could be raised against his justifying comment is given: "But sin is not "δὲ οὐκ" taken into account when there is no law."
3.The apostle rebuts this objection: "Nevertheless, (ἀλλὰ) death reigned from Adam to Moses, even over those who did not sin in the same way by breaking a command as did Adam." This rebuttal draws attention to the fact people died before the Mosaic law was given, and so implies that since death, which came into the world because of sin, was a reality for everyone prior to the time of Moses, the sin of ALL people was also a reality throughout all human history.
My advice to you, Ben, is:
1. Stop reading the KJV because you do not understand it. I am reading the NET Bible, you might find that more helpful, than Shakespearean English in the KJV.
2. Stop trying to make a new doctrine, thinking you have discovered something new, on the basis of a 400 year old translation. The age is important. Because, scholars have studied the KJV up and down and backwards and forwards, and no one has come up with a weird doctrine that there were sinless people living in the world before the Fall. History is important.
3. Read ALL of the Bible to figure out something like "there were people living in the world with no sin" on the basis of a few words out of context. To make a Biblical doctrine, please use Greek. Second, that doctrine must appear in many places, not one. Of course, this doesn't even appear in the verse you posted. But still, when you can post 2 or 5 or 10 verses that say the same thing, then you might be onto something.
So no, you have completely read the verse wrong. I hope that helps.