This restriction is really blocking me. I'd like to comment on a working solution, and confirm that it is working.
I'd like to comment here: How to bring back Photo Viewer in Windows 10?
There really is no trick to getting reputation points. You just have to participate in the SU community by answering question, editing, etc. A good start is to follow some tags that you are knowledgeable about. This will probably help you out.
Like nhinkle said in a comment (how ironic, in a way) to your question, commenting is not how you indicate here that a particular answer worked for you. Instead, the way to do that is to upvote and (if it is your own question) accept an answer.
See What should I do when someone answers my question? in the help center. While the text is written from the perspective of your own question being answered, except for the part on accepting an answer, it is equally valid when reading answers to someone else's question.