Everyone stuck getting this mod to work, try this. Download and replace your old scripthook file. That seemed to be the fix for me.
http://www.dev-c.com/rdr2/scripthookrdr2/
I did also do a clean wipe of the game and start fresh. All I downloaded was the above scripthook along with the latest ASI loader, LML and this navy colt mod. You DO NOT need Lenny's Simple Trainer for it to work.
Make sure you download and install or replace the current version of Lenny's Simple Loader. If you still hear the beeps but crash on load, do what
Entreped in the comments above stated, that was the fix for me.
" You could try using a version.dll that's a year newer...
RDR2 Asi Loader
Version.dll "
I just replaced my Version.dll from lenny's with the RDR2 Asi loaders version and now my game loads fine.
Cheers Entreped!