How do I use the old disk?

Hint 1 of 6:

Do you remember the lessons from the Command Center?

Hint 2 of 6:

Time for a duel.

Hint 3 of 6:

The altered present must be compared to the saved history files.

Hint 4 of 6:

Return at once to the Command Center.

Hint 5 of 6:

Put the Journeyman disk from the past into the right hand player.

Hint 6 of 6:

Let the machine work, and then study the results.