1. How to recognize that PARAM_OBJECT-ed param was a Binary Object (and not for example Sprite Object).
Generally I think you'd have to put a magic number in the target object's CRunObject, and check that that value is expected. I think I can come up with a better system in future though, using the plugin name (which isn't currently available at runtime).
[quote:31gzq68k]2. Is there any reflection mechanysm allowing to access given CRunObject*'s Fields/Properties/Methods?
As you mention, GetData and CallFunction can be implemented to return data like the binary object's buffer - however, the Binary object doesn't have any such implementation yet, I don't think. If you ask Rich for the source to it, I'm sure he can send it to you. Also, if you have the Binary object's CRunObject definition (copy and paste its ExtObject from Main.h and rename it to BinaryObject so it doesn't conflict with your object), you can then cast a CRunObject to a BinaryObject, and directly access its member variables.