No dotted or dashed lines possible with the polyline tool, but getting clever with the texture tool "may" produce a facsimile. I don't use the texture tool on a regular basis, but I'll play with it and see if I can trick it to do something close.
You could also use the array tool with a short line segment to put several in a row to make what looks like a dashed line. Make all the segments a group so they stay and select as one. I don't use different line colors but you could make a strip that was a joined section of black and white (background) color that would act more like a single solid polyline.