in App-V 4.6 you could do this
sfttray /exe cmd.exe "AppName"
"AppName" was the application name not the package name.
in App-V 5.0 the equivalent is
Method 1 (this gives you an elevated cmd windows inside the bubble)
Open an elevated powershell window then
set-executionpolicy unrestricted
Import-Module AppvClient
Get-AppvClientPackage
$package=Get-AppvClientPackage <PackageName>
Start-AppvVirtualProcess -AppvClientObject $package cmd
Method 2 (this gives you a command windows in the context of the session you launched it in)
Locate the GUID string from the folder structure below C:\ProgramData\App-V (perhaps by searching for a known file)
Select up the directory path in the explorer path windows and copy out the PackageGUID\VersionGUID string.
then cmd.exe /appvve:PackageGUID_VersionGUID
(remembering to replace the \ with a _ in the PackageGUID\VersionGUID string.)
(remembering to replace the \ with a _ in the PackageGUID\VersionGUID string.)