Enable Submit button after completing Likert and TextEntry

About the Likert question

Unfortunately, Storyline triggers can't use the Likert buttons. So, for example, a trigger can't check whether the state of any of the Likert buttons is selected. 

This post describes how you can use custom survey questions for special branching or feedback within a course: TIP: Track Responses to Custom Questions or Surveys - Articulate Storyline Discussions - E-Learning Heroes. 

• Note: This tracking is for use within the course. It would not be directly reportable to an LMS/LRS. 
• If you want Storyline to send responses to an LMS, you need to use graded- and/or survey-questions, plus include a Results slide. (Extra programming could report variable values from custom questions. Reporting values is described here :Storyline 360: How to Send the Value of a Variable to an LMS/LRS - Articulate Support).

About the text-entry question

Text-entry fields are given a variable to store what the user types. The default value of that variable is blank. The program won't adjust the variable to the typed text until the field "loses focus." In other words, the user has to click on something outside the text-entry field to update the variable. 

That "something" they click could be your Submit button in its Normal state. And you could still force the user to enter something by adding a condition to the button's trigger.

• The trigger could submit the answer with the condition that the text-entry variable isn't blank. Otherwise, it could show the user a warning that they must enter their answer. For example, if the warning is on a layer, the trigger would look something like this: