Re: parallel lines still crash program
Don't worry - it just is quite a complex area to get debugged and it has been a looong slog and I am quite anxious for it to go out.
My apologies for my response - I sometimes feel in the role of the man who kept the hand-pumped organ in my grandmother's Devon country church full of air - she told me that when a new organist from town came to play one Sunday, after a time the music gave out. A red-faced, puffing head then appeared from round the back of the pipes and yelled "b'aint electric!". :-)
I don't understand the delete key issue fully - but Delete and Backspace are mapped differently on Windows to Mac keyboards - can you try using the "backspace" key instead of delete perhaps?
PS I'm in Northern CA -> once I have it running, I will have lots of need of help operating and all will be welcome once we get through the current unpleasantness. OO Gauge, 1962, a flight of Welsh fancy dripping with "hiraeth", you'll find it under the examples folder -> Port Dinllaen. There's an poorly unmaintained blog with some photos of progress - portdinlleanlines.com