To import times from Summit Timers, you would need to be able to get the log file from your device(s) and onto your computer, then you can set up a File Stream using the Summit Systems Timing File Stream Type.
If you have multiple Summit Timers recording to the same file, then they are identified by the record_num column here:
That will be set in the Device Identifier area of the Stream Setup for Summit File Types:
This way you can have multiple Streams pointing to the same Folder and File, but the reads will be sent to one Stream or another based on what their "record_num" value is.