I'm a little new to cabling but learning quick. I have several harnesses to make with are fabricated from cables which have an overmolded M12 connector at one end and a rectangular multipin connector at the other. The cables are standard 4 conductor cables. I've done good so far making entry ports and spools, wire colors, and designating. I have two harness complete already with 8 pin connector and two 4 conductor cables. Now I have a harness to make which does not use all of the conductors in the cable. I can't see to get Creo to let me only connect some of the pins and leave the others undefined. I don't think this is unusual to reuse a cable spool but not use all conductors.
One approach that seems to work is to first route the entire cable along a network so that both ends are close to your connectors, or wherever you want the entire cable to stop.. At this point, you will just have a cable floating in space. Next, route the individual conductors between your connectors following the same network. The cable will show as incomplete in the model tree, and the unused conductors will also show as incomplete, however the used conductor's will show as complete.
I agree with Aron's approach. But if you like to see the all the cables and conductors complete, you'll have to do a bit more work. What I've done is this. 1) in the schematic you will terminate the unused conductors to a splice or terminal symbol's port. 2) In cabling, add a splice part, if you have one to your routing where the full cable will end. Make sure the TYPE parameter is set to SPLICE before routing to it. Then as you route the cable/conductors, the unterminated conductors will stop at the splice as complete, while the other continue on to your connector. I used a "null" type designation and removed any BOM information regarding the splice used so that it won't show up in the BOM table or other to-from tables.