In a CZ 75 variant with an intact Firing Pin Block (like the SP-01 Tac) there will always be some Single Action pretravel. This is because the FPB requires a certain amount of SA pretravel to function.
The CGW Pro Package includes the Short Reset Kit (SRS) parts. These parts reduce the SA reset distance and SA pretravel while preserving the function of the FPB. To further reduce the SA reset distance, which then allows you to further reduce the SA pretravel, requires a non FPB CZ pistol. CZ 75 variant Decockers models require the FPB to remain intact due to their design and function. CZ 75 variant Safety models are differnt and can be obtained from the factory without FPBs or have their FPBs removed for the models that come with them. These non FPB safety models can then have their SA reset distance and pretravel reduced to the absolute minimum with the correct tuning.
What i have attempted to explain here can be directly observed. If you fully cock the Hammer, then closely observe the rear of the pistol just above the Sear Hammer interface, then slowly press and release the Trigger without dropping the Hammer, you can watch the FPB Lifter Arm travel up and down. This FPB Lifter travel is taking place while you pull through the SA pretravel.
If you have the SRS kit parts correctly installed in your SP-01 Tac, you have reached the minimum SA pretravel generally possible with this CZ75 variant decocker model.