1. Select Tools, Action tracks, Assign Constituent Action Tracks
2. Assign the action track to a single constituent. Click Next.
3. Select where to start the track. Click Next
4. Click Yes in the Do you want to link these actions to a proposal? frame and select the proposal to use.
5. Click Assign track now

The actions that are created as a part of the track re added to the Actions tab of the proposal as well.

note: This works when assigning action tracks to a single constituent, not a query of constituents. This is because each proposal is specific to one constituent.