The equations convert to low resolution images!
This is a technical limitation in how the MathType engine handles equations in export; they’re converted to raster images in the compile process, so are no longer editable and will suffer some quality loss when scaled. I will check on the image resolution and quality in the compile process (compile is still under development); you may want to make sure that the image is at 100% in Word and hasn’t been scaled there. If you need to do further editing to the equations after compile, however, you’ll need to insert them directly into the document in Word.