If the file has not been improperly altered since export, the import wizard will automatically present the TuningFork XML, TuningFork CSV, or TuningFork TXT import strategy (as appropriate) along with one of the more generic strategies. In general, choose the TuningFork strategy if it is presented, as it will produce a more useful result.
Currently, this import strategy will reconstruct any mixture of sample streams and interval streams that may have been exported. This includes derived streams, but those streams come back as base streams (the derivation history is lost). In addition, other stream types (e.g. bookmark streams) are only re-imported as raw events. Some of these details will be improved in future releases.