Computer Design Programs
It was only natural that computer aided design (CAD) programs would be adapted for model railroad use. The big name in this sector is AutoCad, which is an expensive program used for many different types of computer aided design. There are other less expensive programs which allow for quick drawings that are easy to edit.
At one time, there was a product in the American market called PC-Rail which had libraries of different track types, including Märklin Z. This product may still be available in the European market, but it is ancient history here. The big name right now is CADrail from Sandia Software. CADrail includes track libraries for Märklin Z track sections. The learning curve for such software is somewhat steep, but once you have mastered it, layout design becomes quite easy.
At the moment, I am using another program called XTrackCAD. It is open source, which is to say that you will have to do support functions yourself. There is a WIKI on the subject, here. There is a component library of Märklin Z-Scale track, but I have not found a similar library for the Micro-Trains track. Since both lines have similar track geometry, you should be able to substitute with the Märklin library.
One oddity with many of the software packages is that they are very precise, so when you are drawing a track plan, you may end up with a little odd misalignment when you attempt to close an oval of track. Keep in mind that the software generates numbers which are quite precise but that in the real model railroad world, such a misalignment could be “averaged out” over a space of several feet and not be noticed when the layout is operational. This isn’t to say that a gross misalignment should be allowed to stand, but if something slightly odd turns up in a computer generated drawing, you can be content to fix it when you are installing the real track.