I am applying for ITIN number but it take 2 month to get and I receive it end of January 2016. Is the form W8 available after 31st December 2015 to fill or can envato accept it?
You can fill/update and submit W8 form anytime.
Please read this help article for more info.
for applying ITIN I am going to send my original passport instead of sending certify true copy.
Can I send original passport?
Will IRS return it to me after completing process.?