Hello!
Now in Logicity 1.7 you can specify custom variables, formatted to VBScript.
To write your own variable under the Display Name tab, simply put your VBScript command with a pair of percent signs around it(To specify it as a variable) and then a pair of curly brackets inside of those(To specify as VBScript). For example, if you wanted to display the current DateTime you would enter the following: %{Now}%
Now once you run your report, you should see the current DateTime in your Display Name.
I hope this helped!
-Devin