instead of telling us this on that did not work and wanting to solve your issues:
just pick one, only one issue (like freefilesync) and go thru all the steps you made.
I mean you document what did you try, what's happened and we will try to help you to go forward.
But right now we cannot do even a single step, because you had always given up and started to go in a different direction.
So do not list your needs, but how did you try to solve them.
http://www.catb.org/~esr/faqs/smart-...html#beprecise
"Not working" is not an answer, post exactly what did you try and what's happened.
1. dupfinder and similar tools can do that easily.
2. a simple find command can be applied (you can also look for complete solutions on the net)
3. is just meaningless, what is master directory? choose for what?
4. again, what does "remaining" mean?
5. What should be deleted? ..