I just can't replicate the issue with
FolderBrowserDialog.ShowDialog hanging, so I've created a new version of the app (version 9) which has a new 'Prompt for Export Folder' option. Unchecking this option removes the need for the dialog box.
You can download version 9 from my site Alferd Spritesheet Unpacker version 9.
On the 'Options' form untick the 'Prompt for Export Folder' check box and now ASU will just export the files to whatever directory path is in the long textbox at the bottom of the main form.
(If you don't want to change this option every-time you can set
false in the