WSOD when updating event series definition

Testing out the module, and created a simple recurring event series, and saved.
Edited the same event series to change the recurrence definition
Clicked on the "confirm changes" button to delete and re-create

WSOD

Here's the error message:
Drupal\Core\Entity\EntityStorageException: The "" plugin does not exist. Valid plugin IDs for Drupal\recurring_events\EventInstanceCreatorPluginManager are: recurring_events_eventinstance_recreator in Drupal\Core\Entity\Sql\SqlContentEntityStorage->save() (line 811 of /Users/bauman/Sites/iccr-db/web/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php).

And partial stacktrace:

0 = {array} [6]
 file = "~/web/core/lib/Drupal/Component/Plugin/Discovery/DiscoveryCachedTrait.php"
 line = {int} 25
 function = "doGetDefinition"
 class = "Drupal\Core\Plugin\DefaultPluginManager"
 type = "->"
 args = {array} [3]
1 = {array} [6]
 file = "~/web/core/lib/Drupal/Core/Plugin/Factory/ContainerFactory.php"
 line = {int} 16
 function = "getDefinition"
 class = "Drupal\Core\Plugin\DefaultPluginManager"
 type = "->"
 args = {array} [1]
2 = {array} [6]
 file = "~/web/core/lib/Drupal/Component/Plugin/PluginManagerBase.php"
 line = {int} 83
 function = "createInstance"
 class = "Drupal\Core\Plugin\Factory\ContainerFactory"
 type = "->"
 args = {array} [2]
3 = {array} [6]
 file = "~/web/modules/contrib/recurring_events/recurring_events.module"
 line = {int} 224
 function = "createInstance"
 class = "Drupal\Component\Plugin\PluginManagerBase"
 type = "->"
 args = {array} [2]

The root problem here is the "creator_plugin" config value is not initialized, so the call to $active_plugin = $plugin_manager->createInstance($config->get('creator_plugin'), []); craps out.

Recommended solution: fix the install config.