Custom Part imports blurry

Your input svg appears to be poor quality. This is the breadboard from this part

compared to your part (both displayed in Inkscape)

Note that your connectors are not on 0.1in boundaries (i.e. aren’t on the grid) as well, so this won’t show well in Fritzing.

I expect you would be better off to start from the breadboard in the part above and go from there. As well this tutorial may help somewhat

Peter