a. When you have opened a save file, simply clicking "save" should automatically save the file you opened, not ask you to find the folder again and overwrite save files
Sorry but this will never happen there is a chance that you file after editing will not work properly in ff7. since you can break you save just by changing the values in your save.
b. The app should navigate automatically to the save folder by default every time.
This will most likely not happen either since i have no way to correctly predict where ff7 is installed. eventually i may set up some sort of config file to allow you to set you default save folder.
when you set the 'points to next level' to 1, in the game, it doesn't seem to actually level up when the 1 point is given in battle
it should be noted here that any other editor that allows you to set a chars next or exp value does not exactly work. next is only a place holder. exactly what bosola said above about it.