I prepare the immigration application form for my mother. Several questions need your help:

1.I have an immigration package sent by HongKong. And the checklist said that I need to finish "original form".
But I'd like to fill in the form online since it is convenient. I'm not sure if it satisfy "original form" or not to do that.
Can I do that or Do I must use the form given in the mail?

2.In the item "Your mailing address", can i use my home address in Canada? Because currently my mother live in Canada as a visitor and I'm afraid the mail from immigration office in HongKong will not be received if I use China's address.

Thanks very much.