Hello Patricia,
8.3.9 has a lot of really helpful improvements, including better dictionary configuration and direct uploading to
https://webonary.org.
In the upgrade process, have all members do a send/receive with their last changes, then do a send/receive yourself.
Update your version to 8.3.9. When you open your dictionary it will mitgrate to the latest format.
Do a send/receive from your machine
Make sure your team members all upgrade to 8.3.9 and then do a send/receive.
You do need to make sure all team members are using the same version.
Generally speaking, newer versions have bug fixes and improvements that help you and your team have a better experience using FieldWorks. I'm not sure why one would want to keep using the older version. :-)
Best regards,
Paul