Since I am at work I am rattling this off from memory, so if it isn't complete, my apologies.
Place the files in the Rocksim program folder, under data and new.
Restart Rocksim and files will be imported.
Thanks, Layne. I had been wondering about that myself. And thanks, Marlin523, for asking a question that I keep forgetting to ask.
One follow-up question, though, for anyone. I know how to create comma separated value files in Excel; that's easy. But if I wanted to add a whole bunch of parts into RockSim, what would be the sequence of the values that it would need to have for each record? I can easily set up the spreadsheet, but I need to know what values to input. TIA and Happy Holidays!