I used the "Barcode Splitter" tool to split multiplexed RNA-Seq libraries into separate files. I would now like to map the reads from each of these fastq files to a reference genome. However, the fastq files generated by Barcode Splitter don't appear in the "Fastq File" pull-down menus within the the BWA or Bowtie launch pages. I'm probably missing something obvious, but what is the trick for making these files available for the mapping tools? Do I need to import them into my history somehow?