I wrote down all the features you mentioned :)
It will take me some time right now to add new features (kinda busy). I will check whats wrong with the pasting/saving/loading.
Edit:/ Can you try run the app as admin? Maybe this will help. Cuz I do not see any problem with the code, I also have the loading and saving rewriten in alpha 1.1.
Or try loading from path like that "C:\Demo\"
Maybe your user name contains characters the program can't read