It'll sometimes get hung up, happened to me. Check to make sure you actually have th c++ files downloaded. One way to make sure is to download albo's troubleshooter. It doesn't need to be in your root GTA V directory. What I do with this file is just create a new folder on my desktop and extract the files to it.
Once the files are extracted just select "Albo1125's troubleshooter" if it tells you you're missing the 2010 or 2015 c++ redistributsble package you'll want to try to install just the redistributable package through Microsoft's website. Restart your PC after installing the packages. Then rerun the troubleshooter. If it still says you're missing one of those packages you're going to have to install one of the free versions of Microsoft's visual studios. (Currently, that's the only way I've found to get around it)
Restart pc again and rerun the troubleshooter. At this point it shouldn't say anything about the redistributable packages anymore. Close the troubleshooter then do what myself and TheForecaster said and edit your command line for -scOfflineOnly. At that point run your actual GTAV.exe file, load a saved game, go to settings, then go to the startup and launch menu (at the very bottom of settings list) I can't remember what it's called but select the first option to off so you can select the second option on that list, which is load single player only.
Save the game and exit, from there you can try starting rage and see if it's fixed. If it still doesn't launch make sure you actually select in your AV to exclude GTA V and the LSPDFR installer (even if your anti virus software is off, it can still block the files from correctly installing.) At that point, try to reinstall LSPDFR. Once you go through the setup, install the most recent Rage Plugin Hook. Launch rage and it should be working at that point.
Of course, that's just going off of what you posted on my thread earlier how you think we have the same problems. Everything listed above is exactly what I did to fix my problem so if our problems are similar, this should get your game working again.
I apologize for the wall wall of text, just hoping our problems really were the same and we can get it working for you.