As I said, we have encountered cases in which an exception is thrown in the DocumentPosition class. However, those issues are caused by the spell checker decorations and are resolved when disabling the spell checker.
This leads to the conclusion that the problem you observe is different, but we have not been able to reproduce it. Moreover, if the issue was caused by the open command that comes out-of-the-box and any document, we would have noticed it as most of our demos
use Paged layout mode
That said, we would greatly appreciate it if you can open a support ticket and send us additional details about your setup and a sample document which we can use for testing.
Thank you in advance!