I have a hint on how to get that last star, encoded using rot13.com as always:
abgvpr gur ynetr yriry ragenapr ba gur evtug fvqr bs 5,10...
Here is why that hint matters:
lbh arrq gb oevat gjb pngf sebz gur yriry gb gur evtug.
If I find time and motivation, I will probably edit this post to include how to do it. Hope this helps!