Well for one I don’t really see where I am trashing you, for two if you give advice to people when your code looks like swiss cheese then I don’t really know what to tell you. That script doesn’t need a PR it needs to be scrapped and redone from scratch.
Here I’ll link you some litterature if it means you can improve your skills : [TUT] Securing Your Server
Drop the defensive stance and learn to code better, you have half a dozen PAID releases on the forum and if they all look like this under that escrow then I pity whoever purchased anything from your store.