i also don't think that they would care a lot about ur external income since they clearly state in guide/manuals that an employment outside Canada does not guarantee the same employment in Canada, it does not give u Canadian experience, it does not guarantee that u'll find employment fast once u r back, etc; also, they say that they do not have the resources to asses an income gained outside Canada (maybe where u live now that income could cover u for 3 months but in Canada it's not enough for 1 month)
what u need to focus especially being outside Canada is how to convince them that u go back AND plans on how u'll support urself and ur family once u r back (Canadian account statements with enough funds for maybe a few months or family support letters, proof that u started a job search or u did research on how to open the same business in Canada); at least this is how we r approaching it