I had asked this question myself few weeks ago.

From what i understand is Lying at this stage is bad. If you lie and during the background checks and other checks if they find out then that looks like a trouble.

There's a rule called 245k rule where USCIS states that if you do status violation (that includes: Out of status, Unauthorized work etc) not more than 180 days then you can invoke this rule and still qualify for Green Card. However if it's more than 180 days and you haven't re-entered US again in valid non-immigrant visa then that's another problem.

If one re-enters US in a non immigrant visa then USCIS doesn't count prior to last legal entry.

NOTE: These are my understandings only. I am not a Lawyer. Please consult with immigration attorney.