Hey!
I know you can invoke a button using the Value property of a button.

You can try to call the >>> button on the form events.

Lookup the buttons name and use:

 Form.Controls("cmdOK").value = True 

Lokks like this code would executive in the Forms.Current event.  How do I get there using customizer?

Have you ever used the customizer before?

Open the Sales Order Entry screen and click the customizer button on the toolbar (or press Alt F3).

Then, click Script Editor.

Select Form and the Event choose NEW just to test.

Add the code to call the button.

Save everything and you should be done.

Mateusstock:

I think you would want to use the Customizer Script Editor's Form > Activate, rather than Form > New

Tested in v2014, this works :)

1. Open Enter Sales Orders and Quotes

2. Click the customizer Icon "Alt + F3"

3. Click the Script Editor Icon

4. Select Control Name: Form

5. Select Event: Activate

6. In the body type:

    Sub Form_Activate

    Form.Controls("cmdMoreLess").value = True

    End Sub

7. Click Check Syntax to confirm the syntax is correct

8. Close out of Script Editor

9. Save and Exit Customizer