I have recently discovered that the CEPC platform is no longer shipped with Windows Mobile. Unfortunately, the Windows Mobile documentation contains many references to this platform (which you won’t have) and we are working hard on tightening up our documentation. Windows CE (general embedded) customers still have access to the platform.
In the meantime, the CEPC is a Windows CE sample platform that utilizes common, off-the-shelf x86 hardware that can be purchased at most PC retailers. It allows users to quickly and inexpensively build Windows CE devices for development and testing. It is not required for Windows Mobile, but many (including Microsoft) find it a reliable and cost effective platform for development and automation. And the MDDCEPC is simply a variation of the general embedded CEPC platform.
I apologize for any inconvenience or confusion this may have caused our customers.