This process is injected in the pack procedure
Waits until signed files are available.
- pack blender.exe and BlendThumb.dll in tosign.zip and write to_sign on shared drive
- wait for signed file to appear in designated directory.
- unzip to original location
On the signing machine winsigner.py needs to be
running and have access to the signing certificate.
Current proposed winsigner.py can be found at P1137