Yes.
The object reference cannot be enabled while 'GRREAD' is active.
'GRREAD' is like the corner where the Keymaker, the Merovingian, or the Oracle dwell: the rules here are different.
To have an object snap available, it would be necessary to write or implement one (such as Lee Mac's GrSnap, for example).
But this would considerably increase the code, and I think it's unnecessary because, in the second part of the command, object snap is enabled.
PS: I modified the code at the last minute yesterday.
You might want to make sure it matches the version you have.