Hi. Recently my app got rejected from Apple. This was all right few weeks ago. I used 5.1.1.GA and I didn't change anything significant. I also tried to resubmit app with 5.5.0.GA but that didn't go through also.
Also, noticed this is not isolated issue as one more developer experienced the same issue.
Here is response from Apple:
Performance - 2.5.1
Your app uses or references the following non-public APIs:
The use of non-public APIs is not permitted on the App Store because it can lead to a poor user experience should these APIs change.
And more info about error in Ti SDK:
Thank you for your reply. Our team has re-reviewed this app to ensure our findings were accurate, we found this app contains references to the following selectors:
"focus:" was found in the method -[TiRootViewController manuallyRotateToOrientation:duration:]
Please take a look at this asap. Thanks.