
When you click the "+", you'll need to locate the "My Transfer Folder", select it, and press the Add button. Click the "+" to add "My Transfer Folder".

Use the Apple > Preferences menu command to open the Host computer's preferences:.Create a folder on the Host, preferably in an accessible directory like "Documents".Here are the one-time steps to create the shared folder: Once you follow these steps and set this up, you won't have to do this again.

The purpose of a creating a shared folder is to transfer documents between your Mac running Catalina (HOST) and the VirtualBox virtual machine (GUEST) running Mojave versions of Screenwriter 6.5 and/or Dramatica Story Expert 5.3.
