I have a pretty big spotfire page (or "dashboard"). I have been asked to now include it as a page into another spotfire document. Do I have to re-do everything or is there a way to copy paste pages across spotfire files (all files involved have the same underlying data/variables)
Since your data sets are the same, you can simply right click on your page's tab (or any single visualization) and select Copy Active Page / Visualization, then use Edit > Paste on your new DXP to paste it in. Be sure to manage marking and Filter Scheme conflicts accordingly.