OpsMgr 2007: Active Directory Management Pack Checklist
Pete Zerger (of System Center Forum) has composed a checklist to use while importing the Active Directory Management Pack. Obviously, you'll still want to read the Active Directory Management Pack Guide before importing the Management Pack, but this might be useful to jog your memory as you're going through the procedure.
Installation Checklist
Import the Active Directory Server Pack
Create a Management Pack in which to store customizations, such as overrides (for details on why, see this post)
(Optional) Import the Active Directory Client Management Pack and override the AD Client Monitoring Discovery Rule
Enable the Agent Proxy Setting on all Domain Controllers
Configure an account for Replication Monitoring (associated with the Active Directory Management Pack Account Profile)
Create a RunAs account and associate it with the AD MP Account Profile
Optional Configuration
Configure the maximum time allowed for change to replicate across a forest
Disable collection of warnings, performance data, and miscellaneous noncritical events to decrease network traffic
Enable data collection for the Replication Latency Report
Set parameters for tasks
Common Problems
Oomads not installed
Oomads 64-bit issues
Agent proxy settings enabled on all Domain Controllers
AD MP Account Profile Run As Account Password is not validated by the application when entered