Only the pads on the trace side should be connected to the traces. If both sides are connected then the board is plated and that generally means the wrong resistance.
My rationale for having the traces on the bottom is that the solid copper side seems to expand more causing the middle to bow upwards and press flat against the glass. Other people do mount it the other way up though.
My rationale for having the traces on the bottom is that the solid copper side seems to expand more causing the middle to bow upwards and press flat against the glass. Other people do mount it the other way up though.