I would try the following, with the knowledge that it is a custom hack that will need to be reinstated whenever either plugin is updated:

• Reinstate an unmodified working copy of Events Calendar
• Use Plugin Organizer to ensure that Role Scoper loads first.
• Copy user-plug_rs.php into the Events Calendar plugin folder
• Right above any pluggable.php calls in the Events Calendar code, add this:
  include_once( 'user-plug_rs.php' );
• Remove this line from role-scoper.php:
  require_once('user-plug_rs.php');

This should work for any plugin which is not also trying to custom-define the wp_set_current_user function. In that case, you would actually need to merge code from the two customized functions.

Let me know how it works out. Please install the current Role Scoper development version before applying this hack because it contains some changes to user-plug_rs.php which you will need later.

Maybe in a future RS version I can eliminate the pluggable.php sensitivity.