This tools seem to be wonderful, however usually BAM or SAM file is aligned with our specified references sequence, but here we do not get option to select which reference sequence you want to opt or even just selecting SRA and with whom it will align, I am not sure ?
You can map against any reference genome in Galaxy. You’ll need to source the fasta, load it into a Galaxy history, then choose the “from the history” option on the tool form.
For loading the reference genome fasta, you can usually just copy/paste the file URL from a public source into the Upload tool. Or, locally browse and file on your computer and load the file that way.