Executing TS with DHCP certificate requirements

Question

I have this enviroment, where retriving IP from DHCP requires certificate. The certificate script and package is already done, and it has been working earlier, but when I try to create new boot image media, the script executes too fast and IP is not retrived.
If I then execute the script manualy from WinPE, it goes OK and IP is retrived. So problem is here, that for some reason I cannot create the prestage command right.
I have tried 4 different ways;
1. In boot image properties -> customization -> run prestage command.
2. In boot image properties -> customization -> run prestage command with cmd /c
3. While creating boot media, set prestage command.
4. While creating boot media, set prestage command with cmd /c
I have checked, that package sourse and folder directories are porperly set, there is no typo or missleading paths.
Also problem is, that X:\Windows\Temp\smsts.log does not show anything about executing prestage command. 

Answer 1

If cmd is just flashing by, then it's not really delaying.
Not sure what you mean by prestage package?
Prestart commands are simple files added to the boot image within the WIM.
Jason | http://blog.configmgrftw.com
By prestage package, I ment the package I use when I set prestage command in boot media. So I have the package with all files required for import certificate script. And I added the delay to the beginning of main command file which executes entire script
and all components.
I wonder, why I don´t have that package available in WinPE, before TS selection, if I try to search it on command line? If I open boot media .iso, I will see the package too.