Q:

How do I manually define save paths in GMS? 

I want to know if it is possible to set the path for my game's save data in GameMaker: Studio outside of the two default options I am given in the program.  The options I get are:
%LocalAppData%\<game_name>

and
%AppData%\<game_name>

I can't seem to find a text box or text feild that let's me set something different.  I feel like there should be one for advanced users so that path variables and wildcards can be used in the save data path.  
I also tried opening the game's config .gmx and setting the path there.  Unfortunately it did not work as the only values that do work are 0 & 1 which represent the default path options respectively.  Is this possible?  Am I missing something? 

A:

Short answer:
You can't do it. 
Longer answer:
Game Maker Studio does not support a user-specified path for it's game-saving functionality.  However, what you are trying to do is possible with the file system API in GML.  Without using GML, you are limited to using the default paths for game saves. 
Personally, I would use plain text files to save your game data in. 
See also:

manipulating text files in GML
convert real number to string in GML
convert string to real number in GML

