I encountered a weird error migrating a project. The migration went fine, Paratext reported the project had migrated, but then it showed this error when opening the project.
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Paratext internal reference error.png1033×136 6.75 KB
It turned out there were some extra characters in the scripture reference settings (viewed in Paratext 7.5) that was causing this.
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2018_09_27_16_29_23_Scripture_Reference_Settings.png742×493 12.4 KB
When I cleared out the extra characters in Range of verses in 7.5, then deleted the project from 8 and remigrated it, I had no problems.