I think it's just an oil issue as when it warms up it eases upThere are shift/detent pin kits for the ZF gear boxes as they have a problem with the liners/bearings expanding, causing the stiff shifts. The Getrag gear boxes do not have shift/detent pin kits as they don't have the same problem.
@Nodzed your Z3M has the ZF gear box the OP has a Getrag gear box.