Barry: I just received your book DCS WIFI Companion 2nd Edition. I was reading on how to upgrade my TIU and the book you stated Widows PC is required. I use a Mac and I Pad. Will I be able to upgrade my TIU on the Mac or must I use a Windows PC.? I do have one but a turtle is faster. Also I have the 2nd Edition of you DCS Compainion and in your WiFi book foreword you mention the 3rd Edition. Is the 3rd Edition a must to get the most of the WiFi book? I am just getting into the WiFi mode to operate as everything has been packed up for over a year and want to upgrade the software in my TIU now while the layout is under construction. Also can I run PS1 & PS2 locomotives with the WiFi system? How do I determine the current software level in my TIU? Thank you very much.