Registry running state
From WPKG | Open Source Software Deployment and Distribution
By default, when WPKG runs, it changes a registry entry in HKLM\Software\WPKG to indicate the WPKG state to other programs (like logon scripts, which can inform you that the WPKG service is installing software and you should hold on a while).
This can be turned off (it's on by default) by passing /norunningstate to wpkg.js.
HKLM\Software\WPKG\running can be "true" (REG_SZ) or "false".
This feature was introduced in WPKG 0.9.8.