Ok. Paul didn't provide the best link to address your question. The method you used is described in section 7 here:
http://gregmaxey.com/word_tip_pages/repeating_data.html
BTW you can use a method similar what you had done previously. 1) Add a content control, 2) select and bookmark it and 3) Add a Ref field referencing the bookmark.
Yes, there is a "Building Block Gallery" content control and it does by default load the "Quick Parts" building block gallery, but will not repeat data unless mapped to a CustomXMLPart.