How to load Active@ Boot Disk over the network via PXE environment?

Customizing WIM is a complex task, however it can be done. To accomplish this, run the following: (Requires Microsoft's Windows AIK and done from a command prompt)

1. Mount WIM:
   Dism /Mount-Wim /WimFile:D:\ABoot\iso\sources\boot.wim /index:1 /MountDir:D:\!
2. Attach Registry from a file to your local registry, add your values, unload registry:
   reg load HKLM\my D:\!\windows\system32\config\software
   reg add "HKLM\my\Microsoft\Windows NT\CurrentVersion\Fonts" /v "Courier New (TrueType)" /t REG_SZ /d cour.ttf
   reg unload HKLM\my
3. Unmount WIM:
   Dism /unmount-Wim /MountDir:d:\! /Commit

Here is the link to access the Microsoft Windows AIK and documentation

An alternate method is to add a script in to the Boot Disk Creator while preparing bootable media. The script is then automatically launched when WinPE is loading. Here is a link with further details: http://boot-disk.com/booting_disk_drivers.htm.