One of the minor annoyances with farl is the gaps it leaves when you're trying to continue an existing line. I'm using dectorio to put coal-gravel between my rails, and whenever I try and use farl to resume, it leaves a little or a large gap, but usually a little one.

Here's a large-gap example, but it's usually just one block's width, which is annoying :)
http://www.kfs.org/oliver/farl1.png
(I've literally just tapped the forward key briefly and it pulled up a bunch of stuff that it'll never get back to laying down)

and when you're using maintenance mode, it's annoying that it immediately removes a bunch of stuff (including concrete) that will never get laid down, so it would be helpful to be able to tell where farl is going to kick off so you can plan ahead for that?