I took a big risk on a new career, we weren't a good fit, how do I add that to my resume?

I recently took a big risk and "crossed the aisle" from a construction accounting software user, for 19+ years, to a software consultant for a construction accounting software company. From long time user/manager to brand new implementer overnight. Although similar, the software was new to me, as were some of the skills needed to consult for multiple companies. During training I struggled to achieve proficiency at implantation. I also began to realize how many of the day-to-day business processes I would miss by being only a consultant for my clients. I came to the conclusion that the job was not right for me, including the almost constant travel required. I also realized that I wasn't right for the duties I was training for. Amongst other failings, I was too detailed oriented, great for accounting or data analysis, not helpful when you've got four days to expose the entire system to key client personnel. In the end I resigned my position. Once I realized I didn't want continue, I didn't want to waste any more of my company's time and money training me to take on clients, nor did I believe I would do a good job for the company or the client. Regrettably, I never left trainee status, but I learned a tremendous amount about their software and other training/implementation skills. My problem now is I prefer to be open and forthright about my job experience, however, now that I'm at the point of updating my resume, how do I add an entry for a failed attempt at a job? I came away with a lot of new skills and perspectives, but I still never made it past trainee, and ultimately I wasn't good at the job. How to I present that in a positive light? And reflect the positive feelings I have about it? Thank you.