i think there was an earlier post giving a solution for a workaround. adding a boolean[] is indeed not implemented, i guess i forgot. but you can add single boolean values to a message, so if you loop through your boolean array and add each item in the array to the message individually, you get the same effect as adding the array itself to the message.

regarding the objects, i am not sure what you mean by that. objects like your own e.g. processing objects/classes or the values of an object, or soemthing else
the following types are supported for osc as well as oscP5: int, float, string, boolean, character, byte, blob. any other kind of object is not supported but you may double check with the osc specifications. to send objects (serialized) you can use blobs (byte arrays) to do so. but you would need to stick the bytes back together in supercollider so that it becomes a supercollider readable object.
maybe this helps, kind of