[galaxy-dev] Concatenation as first step in workflow

We have samples that span multiple lanes of our sequencer, that are the same sample. We'd like to have workflows where the first step is to concatenation the fastq files for one sample, and then feed it to the rest of our workflow (for RNA Seq). Unfortunately, when I use the Concatenation module as the first step in my worflow, it doesn't have the "Add New Dataset" button appear when running the workflow, and I don't see a way to force it in the workflow editor to "Set at runtime". Is this a bug? Is there a fix forthcoming? Sure I could do this concatenation as a stand-alone module first and then run the workflow separately with my new fastq file, but for my users I'd rather it be part of the workflow. Thanks, Dave