The plugin looked promising but unfortunately there is no documentation how to use it. There are some videos but I only understand every second word and the videos are not structured. I could not find a single video that explains the steps from my CSV file to an imported wordpress post. The narrator keeps showing screens saying they are complicated but I do not need to worry about it?
I also do not know whether this plugin supports custom types as there is no documentation. After about 30 min I stopped trying to figure this out.
My recommendation is to try a different importer until there is any kind of documentation available.