Automator: Change BMP to JPEG files

OK, 25 year software developer veteran, Automator newbie.

Problem: Create automator workflow to convert a whole bunch of Windows BMP files to JPEG.

Looks like the Preview "Change Type of Images" is perfect. But when I create a simple simple "Application" workflow with just this action I get an error every time: No result was returned from some part of this expression. (-2763)

I've also tried adding "Get Specified Finder Items" (which, oddly, Automator tells me I need to add even after I have added it ????). Same error.

Is it just me, or is Automator really this messy to use? It's a nice idea, but it doesnt really seem to glue together too well. Sigh.

Ideas anyone?

Thanks,
Tim