Q:

How to configure/customize a list view to return records for the owner of the record plus users to whom record has been shared? 

The users are shared the record via a custom button which appears as records in a child object. 
There is a parent object A ,child object B ,a custom button is to share the parent records with some users based on territories.. these users are nothing but child records for object B ..,
A list view is to be configured MyEvents so that owner plus the users to whom records has been shared can see.  As there is another functionality for Approvers to whom record is shared has been used in My AEvents(onwer plus users in B and approver of the record) which has been taken care of..

A:

List Views cannot be used to show one-to-many relationships.    When working list views, it is limited to only the object they are run on unless you are using a formula field to reference information on the parent (child-to-parent relationship). 
Reports, however, allow you to join multiple objects together and report on the related detail without issue.    The report type should be available.   If not, you'll have to create a Custom Report Type using Object B and Child Object. 
Here is link for Report Types: https://help.salesforce.com/apex/HTViewHelpDoc?id=reports_defining_report_types.htm
Your last option to achieve your goal is to build a custom visualforce page. 