New Test Parameters

[cflow]

It's actually quite easy for Environment parameters to be created (they are the ones found under "File\Settings\Environment\User-defined" and are visible/editable in ALM/QC).

Code:

'Instantiate the QTP OTA
    Set App = CreateObject("QuickTest.Application")
    App.Launch
    App.Visible = True

'Open a test as required
    App.Open "C:\Program Files\HP\QuickTest Professional\Tests\trial", True

'To add an environment variable to a test
    App.Test.Environment("MyNewParam") = 2

'To change an existing variable just re-write over the variable
    App.Test.Environment("MyNewParam") = "Two"

'Exit safely ;)
App.Test.Save
App.Test.Close
App.Quit
Set App = Nothing

Not sure how you would delete a variable though...
Also not sure why it bypasses the ParameterDefinitions methods or if they are different in a way that would benefit the user to use them separately.