for the number of family members, place two (2) for sponsor and principal applicant. IF you have non-accompanying dependents, do not add them to the app. IF you have accompanying dependents, for example, you have one (1) child who is not a pr or canadian citizen who will be receiving PR the same time as you, add him/her to the app. so in this example you type in three (3). hope this works for you! if not, try to use uci number or other combinations, try adding all dependents, or try to fill single as marital status (i don't know why but it worked for some).