I just spent several hours trying to get the feed wires for the patch example to appear. I *did* finally figure it out, but I'm not sure I'll be able to do it next time.
It actually looks to be pretty well thought out and implemented on the physics side. Perhaps they'll open source the Tcl/Tk UI. As an example of the issues. Once you get into zoom, rotate, pan or similar modes there is no obvious way to get out of it except to quit the program! In the right mouse menu for those options, "quit" doesn't get you out of that mode, it exits the program. And it does some input project updates without telling you at other points in the program. So the only safe way to modify some prior work is to make a copy and work on the copy.
As an example of the UI issues, if you get a plot of Z(f) and you zoom in, you no longer have any scales. And you do not have any control over the scales so far as I can tell. However, at least some of the output can be exported in ASCII so you can make publication quality figures with gnuplot.
I'm a science and systems guy. I worked with a guy who was *really* good at UI design. He couldn't touch me on the systems side, but I couldn't touch him on the UI side. Working with him for 3 years was very educational.
Your comment about needing to do a patch antenna model made me go look at HOBBIES again. I'd already requested and been granted a return by Amazon. But I'm beginning to reconsider the return.