If one or more custom fields have been created for Participant - and added to a Profile... if you use Batch Update via Profile from Find Participants - existing custom field values are not retrieved as defaults for the custom fields.
- create custom data group: used for = Participant
- add a text field : eg. Booth Name
- create a Profile : Participant Info
- put the custom field in that profile
- edit an existing contact's participant record and save a value for "Booth Name"
- now use Find Participants to find that contact/participant
- use Batch Update via Profile
- the row for your "updated" contact will NOT have a value in the Booth Name field
- This problem only seems to affect CUSTOM FIELDS. I tested the behavior for participant Source and Role - and both values for these fields are populated correctly in the grid rows
- Saving a new value to the custom field from the grid works properly
- I also tested this same case for Contribution custom fields - and it works properly for that component