That is poor advise. Microcap is mature software, there is nothing to fix. Just be happy the author made it available for free after having made a living from Microcap for decades. And very likely Microcap is way better compared to using Kicad / ngspice or Ltspice.
I am happy that the author made it available, but after a few goes at it, I went back to LTspice. A small reason was that I have been using LTspice for many years and have many things already done, including several scripts for optimization and so forth (which just process spice source files and data, using the CLI). A big reason was that I had many more convergence problems with Microcap, and this became a showstopper for me. These were mostly switching power converters that I had trouble with.
Perhaps I could have figured this out, but I have so much time into LTspice that it wasn't worth it to me to switch to Microcap. However, I have found the latter to be a great source of models.
John