One other clarification. It's not that conversion software can't create a D1 file, the sticking point is that the floppy is reformatted in a specific way that the D1 will read. I am a retired Sr. Software Engineer with 35 years experience. I futzed around with this trying to create the proprietary file structure and finally gave up. YOu need the software that will format the floppy and move the file, not just translate the file for you to copy.
Also, as someone else mentioned, 3D and 4D will only run on windows 95 or lower. I just kept an older machine for this purpose.