Here are more detailed instructions for converting AppleScripts from 32-bit to 64-bit, in case it's helpful to anyone:
- Open AppleScript in Script Editor
- File > Export > File Format: Application > Save
OR
File > Duplicate > Save > File Format: Application
- Confirm by checking Get Info (Command-I). If there is an option to “Open in 32-bit mode”, that means the AppleScript has been successfully converted to 64-bit.
If the above fails, look for odd characters in the AppleScript name such as the "/" in "ePub Zip/Unzip". Delete the problematic character. You can rename the AppleScript after it's converted to 64-bit.
To add custom icon:
- Open Get Info window for both old 32-bit and new 64-bit AppleScripts.
- Click on the desired icon in the upper left corner of the 32-bit app and copy.
- Click on the generic icon in the upper left corner of the 64-bit app and paste.
Note: This works for macOS High Sierra. It should also work with Mojave. Earlier versions may work differently or not work at all.