When scheduling a meeting, how to obtain schedulerUniqueId of particular user to use in ScheduleParams? #

If you unique id of user scheduling a meeting is not available, you can skip setting this field and set his username (user id) in schedulerUserId field. If you don't have username or unique user id, you can use findUserProfileList method from UserService to search for user based on other parameters: first name, last name, email, profile id, etc.

How to subscribe for notifications for all meetings in the system? #

All event services have subscribeForAllResources method that allows subscribing for all notifications in the system.

How to subscribe for "sharing application" event in Cisco Unified MeetingPlace SOAP API? #

Sharing application event is not supported in Cisco Unified MeetingPlace.

I can't authenticate profiles registered on Cisco Unified Call Manager using LoginService checkUserCredentials method #

Before local user can be authenticated using MeetingPlace SOAP API, his profile needs to be synchronized with MeetingPlace server. This is handled by Directory Service, which can be configured on Adminstration Center, in Directory Service Configuration under User Configuration section.