What exactly do you mean by taking a pic of Titles and the Transitions? You also said preview. There is only one picture preview and one movie preview.To me it sounds like you are trying to put several previews in the same folder. Nope. That won't work. As far as the movie preview goes, here are the simple steps to make it.
MAKING A MOVIE PREVIEW
1) Open up your project/template
2) Hit publish template from the file menu. (if you are in FCP generator, hit save as)
3) If you want to publish a template, select save preview movie, then save.
4) If you want to save it as a generator, well, just select Publish as Final Cut Generator.
In the Motion Startup window, the red box is where the templates are saved. The yellow box is where the generators are saved.
Of course you can always move the files of the templates/generators if you make a mistake.
The movie preview shows up where the red box is and the blue box is where the image preview is.
Hope I was helpful,
~AJ