Dadsvelac is correct about the full color cards are not sharp at all on both Letter & A4. The artwork seems washed out against the color background. Also, on the print friendly Letter size they are also dull where as they are sharp on the A4 sheets.
Finally, for duplex printing of the instruction cards the back-side should be in mirror image of the front-side (example: if the A4 multiplayer cards are center + right on front then they need to left + center on back). This holds true for the letter size sheets as well.
Looking forward to an updated download being sent to my email address ASAP.
Regards,
Grejam53