The following blogs posts describe the creation of a Custom Configuration for MicroStation, they should be read in conjunction with the wikis in the second list:

CONNECT Edition - Custom Configuration - Part 1 : Initial Creation Steps

CONNECT Edition - Custom Configuration - Part 2 : Standards Folders

CONNECT Edition - Custom Configuration - Part 3 : Standards CFG Files

CONNECT Edition - Custom Configuration - Part 4 : Standards CFG File Contents

CONNECT Edition - Custom Configuration - Part 5 : Separating Project Data from Standards

Additional steps required for AECOsim Building Designer are described in the wikis

CONNECT Edition - Create Organization folders

CONNECT Edition - Create a new WorkSpace

CONNECT Edition - Create a new WorkSet template

CONNECT Edition - Create a new WorkSet