RedPhoenixKatherine

I was having the insufficient permissions crash too, I figured out it was the game and not my mods. So not expecting a reply I reached out to Rockstar and they told me to run Rockstar launcher as an administrator. I was dubious but battle eye already has kernel level access and my antivirus/security can monitor programs running with elevated privlidges, so f**k it.
 
It actually worked (from research it doesn't work for everyone) and GTA mow runs fine. Though damn Rockstar updated the game again so as you said were in for a wait.

So I had a thought, Rockstar launcher runs in administrator mode maybe that’s what’s causing my issues. I didn’t want to reduce its privileges because knowing Rockstar that’d mess things up more.
 
So I gave RPH administrator privileges and it worked. It launched the game quick and hooked in straight away and loaded LSPDFR without issue.
 
Now I just have the fun of re-modding the game but that whilst time consuming is fun. I’m looking forward to getting back on patrol and I’m going to try setting up custom agencies (Rockford Hills PD, Del Perro PD and USAF PD) and see what I can do
 
Thanking you all for the support I know I would have received if I hadn’t managed to fix it myself.

I found the error, I'll leave this post up in case it helps someone else
 
In this line I did the end tag wrong (I copy and paste so how I did this I don't know lol)
 
<Item>dlcpacks:/sahp_JusMe/<Item>
 
It should be
 
<Item>dlcpacks:/sahp_JusMe/</Item>
 
Hope this helps anyone who's in a similar spot and thanks to everyone who has helped me