I'm also applying for the licensure of NY and having the same question....
But I just answered "NO" to that question on Form 1. Casue I'm a non-US educated applicant and I didn't need to take the SBPT nor the NCLEX examination in order to get my license. No such information about the exam results can be provided by my licensing authority. So I didn't complete the Form 3.
I think it's alright, cause CGFNS will forward the verification of licensure to them later.
( I just guess, but many people say only Form 1 is needed for the foreign student.)
I'm submitting the Form 1 and CVS application forms at the same time as instructed by CGFNS. So I already finished that course and certificate will be sent to NYSED electronically. I think you can take it anytime just before you filling out Form 1, cause you have to answer the question no.24 on Form 1.