My FCPX 10.1.2 magnetic timeline stopped working.

Jackie, you have many connected clips connected to a gap clip in the primary storyline. if you want the clips to ripple automatically, select the clips in question and create a secondary storyline.

Russ

All clips must connect to the primary story line. In your project, a gap clip is on the primary storyline. Connected clips will not ripple automatically unless they are turned into secondary story lines or a compound clip. To make a secondary, select your clips and right click. Choose create new storyline.

Russ

Russ is absolutely right.

The long completely black clip at the very bottom of your screenshot is a "gap clip". That is the one thing in the primary storyline (that we can see).

Everything else is connected to it.

You may create a secondary storyline, as Russ wrote. But then the titles above would still be connected to the gap clip at the bottom and not to the other clips, as I suppose you'd want them.

A better alternative would perhaps be to select all the clips just above the gap clip and do "Overwrite to the Primary Storyline".

I recommend that you take the time to familiarize yourself more thoroughly with the concepts.

The excellent course by IzzyVideo is a very good way to learn the basics of the magnetic timeline, connected clips, secondary storylines, etc.

http://www.izzyvideo.com/final-cut-pro-x-tutorial/