Is it necessary to obtain ONC Certificate for a customized OpenEMR?

Hello,

We are using OpenEMR with some of the custom changes as below:

  1. Using our own logo.
  2. Changed the Styles.
  3. We are also planning to do some customizations to our OpenEMR.

So, with all the above changes, Is our OpenEMR still ONC Ambulatory certified or we need to go for a certification, as we made the changes?

Could some one clarify me on this?

Thank you