Note that if you choose too large a value for centimeters per unit branch length, the tree will be so big it will overrun the plotting area and may cause failure of the diagram to display properly. Too small a value will cause the tree to be a nearly invisible dot. For the moment I do not allow you to specify left and right margins separately, or top and bottom margins separately. In the next release I hope to do so, so that you can plot several trees on one plot, or plot one tree across several pieces of paper. On output devices where line thicknesses can be varied, the thickness of the tree lines will automatically be adjusted to be proportional to the character height, which is an additional reason you may want to change character height.
Regularization is on by default.
It will lead to a tree in which angles look very regular. You may or may not want that. The default is the Hershey stroke font provided in the font file. You can also specify any other font available to you on the Laserwriter. However I have only been able to get Courier, Times-Roman, and Helvetica to work on mine.