First, open up Config Tool (not Security Desk). You can type "Config Tool" in the Windows search bar.

Next, hover over the 'System' icon. Then select Schedules.

In the bottom right, select the "+ Schedule" button.

In the Date Coverage dropdown, select Specific. Then click the Plus button at the bottom.

Click to select the dates that you want, then hit Save.

In the Time Coverage dropdown, select Range.

Use the right click to Remove, and left click to Add. Do this until you've created the window of time you want it unlocked. Then when you're done, hit Apply.

Click the Identity tab, and rename the Schedule to "Bldg Abbrev. + name corresp. to event. (For example, ERES Band Concert)

Return to the Config tool menu. This time, click Area View.

Find the door that you want to apply the Unlock Schedule to. Then click the Unlock Schedules tab.

Search and select the Unlock Schedule by name, and click Select. 

You should now see it in the list. That's all there is to it!