Why sequences didn't export is curious. Use the 64-bit VP release. It is best for lengthy or complex projects.
One way you might go at this is to create a sequence, then export it. Clear the timeline and create another ... and so on.
When all sequences are ready, assemble them for the final sequence, then add subs and dates.
At each step, Save Project File AS, giving it a unique # or name, so as not to overwrite prior saves. Using Save Project Files (no AS) will overwrite. From the HOME tab, that choice is available by clicking the caret to the right of the Save Project button on the toolbar. That's protection, should something go awry.