Windows PE + Install MSI programm

Hello.
I Want boot from Windows PE, and install Kerio VPN Client and veeam Backup EndPoint.
but this app is just msi pakages.
and after boot Win PE i want Install MSI packages.
Becouse after install vpn client cteate virtual network, and i can connet to VPN Server.
I try add files msi.dll and msiexec.exe ito boot.wim and after boot WinPE i just msiexec /regserver, and after take install my VPN Client.
But its not work with WinPe x64. But i want WinPe x64 becouse Veeam have x64 architecture.
How i can do this? Install MSI to WinPe x64?
tnx.

PS What this http:// w7pese.cwcodes.net/Projects/Win7PESE /Components/msi.script (MSI Installer)

PS What this http:// w7pese.cwcodes.net/Projects/Win7PESE /Components/msi.script (MSI Installer)

that plugin allows you to run the MSI installer you are looking to run..
Adds MSI support to PE

This reason my problem?
How i can use this plug for my Win PE? are you have manual?

add plugin to your PE
to add support for running the msi installer(s)

Ok, How add plugin?
What is programm use or where copy file?

msi plugin is already include and enabled by default, in Win7PESE package.
If you already have worries to find 'MSI installer' in components folder, it may be difficult for your VPN. Good luck 

I found some issues with specific msi installations, so I ran ProcMon and filtered out everything but NAME_NOT_FOUND and FileCreate and path starting with X:\Windows\system32...

This massively helps with dependencies. But even after all deps met I still found some issues with the Publishing Product Information.... as it likes to hang.