The multilingual support is planned for the beginning of February. You can try to turn off the multilingual mode the Sitefinity 3.7 so the project runs only in the default language and then run the migration.
Will it be possible for you to send us your project so that we use it for testing while working on the multilingual support?
All the best,
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
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