How to import vector files into EzCad 2 (fiber laser printing software)?

Question

lasers

I tried many formats but neither SVG nor AI nor EPS nor PLT open normally in EzCad2. Everything is crooked - the drawings deteriorate, a bunch of additional lines appear.
How to convert correctly so that vector files do not deteriorate?
I found one article on Harbr ( https://habr.com/ru/post/438466/), but the method described there does not work for me. New version of Inkscape (under Mojave) doesn't save Optimized SVG files, throws an error.