Hello!

This is really basic script.
It will allow you to save anywhere, but dont save while you are in mission or side mission.
The game will crash if you try to save while on mission.
It will save the location you are at.

Using:

While in-game, press Number 5 and not Numpad 5 :)
After that save game menu will show up.
Choose slot you wanne save and wola.