Hi Raisa,Raisa Nazrana said:Rain Forest,
There is no way that you could just forgot to mention about the rejection of USA visa. Now why i started to talk like this? Because your mistake is very much a serious one. In the main global forum there are some reports same as you. And all of those applicants were rejected & were also issued a minimum of 2 year BAN. Now what can you do? Immediately fill up a new background declaration the upload it to below link. There describe about your mistake and say how much sorry you are! it should be in a humble & polite way. Don't just say you forgot. Cozz definitely this word will let you to rejection. Believe me it happened. So think of a good explanation. If CIC accepts then you are lucky.
NEVER EVER MISREPRESENT ANY INFORMATION NO MATTER WHICH COUNTRY YOU ARE APPLYING FOR.
I could not find such a form that you can add your Visa rejection event.