like i said, It wont show up on the temp gauge as overheating all the time. It will start to pressurize the cooling system under boost and during the power stroke. Not always will coolant go into the cylinder.
Id say just stop messing with it and risking it and pull the head off, put a new gasket and get some good studs like the Golden Eagles or Mazorx. If your using ARP's or stock bolts you might not have gotten the gasket seated good especially if you didnt do the first torque sequence 3-4 times before going to the 90 deg or going to the torque value.
The GE studs give you an awesome tightening sequence that really gets the metal gaskets to smash down correctly and fully before going to the final torques on them.
The ARP's if thats what your using could be causing your problems as well with the head lifting or studs pulling threads from the block.
Again i dont know your entire setup but id say stop messing with it and take the head off. There is no other reason for it to loose coolant other than if you had a bad cap but i hope you changed that already, if not thats your last hope.