If you have a VHF radio with the correct frequency and know how to drive on active logging roads (ie: find the pullouts way before you meet any loaded trucks) there no reason they can keep you from using the road. There may not be any spots to park though, you would be best to talk to someone from Downie or the logging contractor to find out. But, if you don't have a radio don't try it, the last thing you want is to be wrapped around a loaded logging truck (and it is illegal to ride a snowmobile on plowed roads - the MOF or RCMP can fine you - let alone it insanely dangerous).