Let's get an actual professional Dev's perspective.
(I will not go much into specifics about LSPDFR)
TL;DR: Unrealistic Expectations
You're getting FREE software, expecting premium features. LSPDFR is a completely free mod, so no, they don't have to provide proper support for it. Support for free products is provided by people in the community who care about it (for example, in this case, the RPH discord or even these forums). You can't expect someone that doesn't get paid to provide a product and also expect them to pay people to make a support team for you. Expecting someone to both give you something and spend money as well for you is extremely unrealistic to say the least.
I would assume you would know about this, but let me introduce you to the concept of bugs. It's pretty clear that you either have never worked on a big project before or got a huge ego. It's extremely common to have bugs when adding new things. Having bugs when adding new things is inevitable imo and in most devs' opinion really. And because I'm really used to getting this unrealistic expectation and I give this reply way too often, I know the question "Why do they publicly release it then?" is coming. They publicly release it, because they most likely weren't aware of the bug when they did and it was either not a really gamebreaking bug or they essentially needed more testers for it (all of us trying the mod out), because it was a tough bug to figure out.
That being said, I'm REALLY looking forward to you realizing that for yourself if/when your game is out.
Considering all the false expectations I mentioned above, I wouldn't say you can properly criticize someone "as a dev", but rather a picky customer (that's not even a customer, because you don't even pay for anything).
First, I really doubt someone that can't set up a mod can create a better version of it, when numerous people most of which don't even have a coding background managed to do it just fine. Second, your respect for the devs is clearly not shown in this post, when you claim you can do better than a whole team of devs. Third, I really doubt you can help, because, again, you can't even set it up.
That's about all of the things I could understand with the lack of punctuation in the post.
I'll give you this piece of advice, if you're actually making your own game: You will get a lot of people like yourself saying the same things about your software and it will be true, so get ready to randomly read this post in a couple years and think "There's no way I expected that, that's so embarrassing" and proceed to delete it out of shame.