After clicking the 'Convert Studio to SVG' button, the page will be re-freshed, and a download link to the SVG file will appear just below the button.
The 'sewing machine1.studio3' is being converted to an SVG file, but the converted SVG file is appearing instead.
It appears blank, since the original drawing is off the mat, and browsers won't display anything off the mat.
To save the SVG file, right clight and select 'Save Link As' or 'Save Target As'.
Ian