OS Version: N/A
Root Cause: File permission problem when trying to create sub directories under C:/Program Files (x86).
Update to a fix version listed below or a newer version if available.
Fix Status: In Progress
Automation Engine 12.2.0 - Planned release date: 2018-06-19
Automation Engine 12.1.1 - Available
Automation.Engine 12.0.4 - Available
Automation.Engine 11.2.7 - Available
Modify file permissions to get around this.
As far as changing the Base64JarClassLoader, add a check to see if the path contains "Program Files", if it does then use user.home.
This way the restrictions will only happen to users who install in "Program Files" or "Program Files (x86)".