The 4 Rozen Maiden titles. Starting from the left, Rozen Maiden (2004), Rozen Maiden: Träumend (2005), Rozen Maiden: Ouvertüre (2006), and Rozen Maiden: Zurückspulen (2013)
Originally Posted by Wikipedia
The recent Rozen Maiden (2013) differs from the previous seasons since it is based on the manga. Thus, it doesn't matter if you've seen the previous Rozen Maiden anime or not - but at least a minimum amount of knowlege on the manga is necessary, especially if you were confused with the first episode of Rozen Maiden (2013)
The first episode of Rozen Maiden (2013) was a recap of all major events from the manga volume 1 to volume 7 (Based on the Shueisha/Young Jump Comics, which is the 2nd edition. If you count the Gentousha/Birz Comics which is the 1st edition, then it is 8 volumes in total). Basically, it squeezed 7 comic books in a 24 minute episode - so it's not surprising that the pacing was extremely quick, and many were confused on the sudden turn of events every 5 minutes. Even though I knew the plot, I had to go back and check the manga to refresh my memory.
However, starting from episode 2, things started to slow down. Focusing on the story after the 7th volume, they are now depicting plenty of details and taking it a bit slow. I liked what they did with episode 2 - they took time to show Jun's character and personality as a college student, and the mystery of the doll parts being delivered to him. They're making a firm base to build the next part of the story on, so I'm looking forward to how they'll do from here.