Re: cloning or making template - whats the difference please
Difficult to understand your first question fully, but from what I can make out, no this shouldn't cause a problem. It's up to you if you want to publish as you go along, it depends how long it takes you to complete the site. I prefer to build as I go, but only because I can build a site from 1 to 3 days, so chances are it wont get picked up by the search engines before I want it to. It is better to publish as you go along (in my view) as you can see how it all comes together and check everything works as should. To be honest, even getting up by the search engines before youfinish isn't too much of a problem anyway.
You can publish away, and if you want to go back and add or make changes, just publish those pages again and it will update.
Don't aim for success if you want it; just do what you love and believe in, and it will come naturally.