If PDF document paper size is for example A0 (841 x 1189 mm) OLE object can be created and application shows PDF content correctly. But if application saves it's document and reopens it Reader does not draw content of embedded PDF document any more. Decreasing PDF document size to A1 solves the problem. Embedded object is not corrupted because it is possible to open it to Reader.
I'm confused why Acrobat Reader OLE server is capable of drawing PDF file content in creation phase but not later on when application opens same file containing embedded PDF objects.
"Application" means all possible application that has OLE support. I have tried this with three different applications and the behavior is same with all applications. Because of this I assume that application I'm developing does not have bug.