In case anyone was interested, I figured it out. Capture One told me to experiment in the print dialog, but there are no options for this there. I ended up creating different page 'lengths', for example, one 8x10 is 10" (the width of the roll) x 8". For two 8x10s, it's 10" x 16", three is 10" x 24", etc. So, I have different 10" wide page lengths for everything from 1 8x10 up to 10 8x10s. After selecting the page size, I then set the number of rows on the sheet to the number of prints I want to make, i.e. 8 rows for 8 prints. They print successfully with no gaps in between. I actually set the paper size as 10.2" wide rather than 10 to create borderless prints. Works great!
Cheers