I did a line of elastic thread in the bobbin and regular thread in the top, with my tension set at the highest on the bobbin, and my stitch width set at 2.5 and then 3.0.... My bobbin thread keeps getting bunched, and it isn't pulling it at all. No bunching is happening... What am I doing wrong? :(

Your bobbin tension might be too tight. I don't mess with mine when I do it. :)

Same here, I didn't touch the tension at all.

I made sure the elastic went on real tight on the bobbin and use a walking foot (I don't think you have to do this but it worked with me). My stitch length set at 3.5. When you start maybe try holding both threads back behind tight so they won't bunch up underneath.