This preference is related to the "Baselines" feature (Reports -> Baselines... menu item). There is a help section tab when you select this feature. It reads:
What is the Baselines feature?
When enabled, this feature simply displays the Change (Chg) column on the Standings Report. The Change column will indicate how much an entry (i.e., bracket) has moved since the previous baseline.
Think of this feature in the same way as you would see a stock’s price move from day to day.
Example: Carina’s bracket was in 10th place after the first day of tournament games and Christopher’s bracket was in 1st. After the second day of games, Carina moved up to 2nd place while Christopher fell to 20th. Carina’s Change column will now reflect a movement of +8 while Christopher’s stock has dropped 19 spots (-19).
How do I enable this feature?
From the PREFERENCES tab of this dialog you would select the Show Movement Reports checkbox. For the Change column to show up, however, you will need to have created at least two “baselines” from the BASELINES tab.
If you would like this dialog to automatically display at certain times while filling out The Results bracket manually, select the Prompt when entering The Results checkbox. When selected and you are manually filling in The Results (does not prompt when the download results feature) this dialog will display at the intervals indicated in the Teams left in tournament field.
How and When do I create a Baseline?
In addition to having the application prompt you to create a baseline, you can also create one manually. To create a baseline, select the Create Baseline button on the BASELINES tab.
When to create is entirely up to the pool manager and will need to be done manually. Typically, you would create a baseline after each day the games are played.
1) If you are using this feature you will first create a baseline and then create the standings report (or build the web site). Once two baselines have been set, this column will then show up on the reports which use this field.
2) If you forget to create a baseline at any time it may be best to just start over by deleting all the baselines and starting from scratch. You would then need to change the tournament results (The Results bracket) to the point where you want the first baseline, set the baseline, change the results again, set the baseline again and then create the standings report. Remember, you need at least two baselines in order to see any sort of movement.
3) If this feature is still confusing you may just want to skip using this feature. If you are going to use this feature don’t forget to enable the Change field on the appropriate reports.