Glad to hear it worked out well, and thanks for taking the time to let us know the fix
I'll explain basically what my programs do with regard to those ConfigDir files, for others that might stumble across this same problem.
When Screenshot Captor (or other programs i've written) start up, the first thing they look for is a ConfigDir.ini file. This file should not be created automatically during installation, so if it exists, its because user made it, so it takes precedence. If this file doesn't exist, the program will then check for a ConfigDir_Default.ini. This is useful because in my portable zips, i include one of these that says to save configuration settings in the current directory (that is, to run portably).
As an aside, the reason that the portable versions come with a ConfigDir_Default.ini and not a Configdir.ini is so that users can make their own ConfigDir.ini that takes precedence, which won't be overwritten if they unpack a new release on top of the old.
So the ConfigDir_Default.ini that comes in the portable zips explicitly says to save settings in the current directory. Without that, the program will choose to use the users local documents directory.
So when you made your own ConfigDir.ini and
COMMENTED OUT the lines that said to run portably, that combination was telling the program to save in users local documents directory, since that's the default behavior of the program if nothing tells it any differently.