To do what ?
Does the messagebox say what it wants permission to do ?
ie, create a folder ? read a file ? write a file, etc.
Did you switch off trial mode before you made the disk images?
It may be an attempt while in Pro Trial to access the cloud license server.
See: How to Skip Pro trial mode in SketchUp Make
For information:
When SketchUp starts the first time, for each user, it needs to create folders in the user’s %AppData% path at:
“%AppData%/SketchUp/SketchUp 2015/SketchUp”
It needs to create sub-folders:
Classifications
Plugins
Gems32 (or Gems64 for the 64-bit edition. The creation of this folder may not happen until a gem installation is actually needed.)
It then needs to copy files and folders …
from:
“%ProgramFiles%/SketchUp/SketchUp 2015/ShippedClassifications”
to:
“%AppData%/SketchUp/SketchUp 2015/SketchUp/Classifications”
from:
“%ProgramFiles%/SketchUp/SketchUp 2015/ShippedExtensions”
to:
“%AppData%/SketchUp/SketchUp 2015/SketchUp/Plugins”
Then SketchUp must also create and setup it’s application key in the user’s hive of the registry at:
“HKEY_CURRENT_USER\\Software\\SketchUp\\SketchUp 2015”
Make this happens correctly for each user’s account upon first running SketchUp.