I have a similar issue, with a much broader error. here is the message. I've don't see a way to attach my race results file. I started with the default career and I'm running the latest version of the app.

Season file validation failed: $.adaptiveAIEnabled: Missing required field: adaptiveAIEnabled $.adaptiveAIDifficulty: Missing required field: adaptiveAIDifficulty $.aiCarClassIds: Missing required field: aiCarClassIds $.avoidUser: Missing required field: avoidUser $.carId: Missing required field: carId $.carSettings: Missing required field: carSettings $.category_id: Missing required field: category_id $.damage_model: Missing required field: damage_model $.gridPosition: Missing required field: gridPosition $.max_drivers: Missing required field: max_drivers $.multiclassType: Missing required field: multiclassType $.practice_length: Missing required field: practice_length $.qualify_laps: Missing required field: qualify_laps $.qualify_length: Missing required field: qualify_length $.race_laps: Missing required field: race_laps $.race_length_type: Missing required field: race_length_type $.race_length: Missing required field: race_length $.restarts: Missing required field: restarts $.rolling_starts: Missing required field: rolling_starts $.rosterName: Missing required field: rosterName $.subsessions: Missing required field: subsessions $.time_of_day: Missing required field: time_of_day $.track_state: Missing required field: track_state $.points_system_id: Missing required field: points_system_id $.name: Missing required field: name $.events: Missing required field: events