Modify Tag

This is probably easy but I can't make it work. I want to take the contents of the Comment field, and add it to the Title such as -- Title (Comment). Can someone help?

I doubt that you had a look at the FAqs:
instead of xyz use (%comment%)

It doesn't matter what I put in what fields, nothing works. And . . . your sarcasm didn't help.

Well the instructions there work for others that have taken the time to carefully follow them step by step, perhaps with a bit of trial and error, making sure to have read the help docs, FAQ etc.

And no one can help you further unless you are more specific about the steps you followed, the results you observed as opposed to what you expected etc. in sufficient detail for them to reproduced your outcome and point out where either you or (less likely) the software went wrong.

Meta comment - people are donating (to you) their valuable time to help, and for free, it's not like you're a paying customer are you? Not just here but generally online, the higher the quality of the brains providing answers the thicker skin needed by newbies. I highly recommend your reading this.

So again, you did not read the FAQs , right?

Because the linked entry ( /t/967/1 refers to an action that you have to create. There are no fields for input, only entry boxes in a dialogue.
Instead of the "%commetn% xyz" from the FAQs enter (if your example is still valid)
%title% (%comment%)