How has FileMaker behaved so far in your testing of this situation? What have you already tried?
Have you tried using a global to view the related data?
It sounds like you're running into a record commit issue. When a user edits a record, the changes he makes aren't seen by the other users until they're committed to the database. If that's the case, you might need to put a Script Trigger on the radio button to commit the record as soon as the user makes a selection. Might solve it.
Yes... Peter is right.
When editing a portal you also have the record you are viewing open unless the relationship to the data is via a global field relationship.
What you need is a script step attached to the buttons scripts which commits the record after changing the values. The smallest amount of time that the records are open the better.
If summary values in the portal have not updated, you can add a script loop which just goes to the summary field in the first portal row then to the same field in the nest row until the last row when it exists and commits.
I will go through your posts and get back to you next week. I will be out for a few days.
Looking into your problem it seems like you are hanging in a solution of record locking while more than 1 user try to edit the same record. This cannot be possible as if you want to lock the record for User-1 by flagging current record the commit of record will not reflect to user-2 unless that user refresh his/her open window/ the related portal. Again suppose User-1 is editing the same record at the same time User-2 cannot able to commit the recent modifications done for the same record unless or until the User-1 release that particular record. This is a data integrity property of Database.
If you want to allow this type of modifications then you need to create a temporary table where you provide set of records for the same table for each user and once an user finished modification on the particular field it will trigger a script to update the original record in the actual table. This will help you to provide the feature you are searching for.
Software Developer, Mindfire Solutions, India