Magome to Tsumago trail

Which is the best direction to walk between Magome and Tsumago?

Both directions are nice. The pass is located closer to Magome than Tsumago. So, you walk for uphill than downhill when walking from Tsumago to Magome and the other way around.

Gerry, We did it in February in the snow. It was very peaceful, almost isolated. We only saw a few people the whole way. There is a trap and that is transport at either end. Do your homework on that one. Tsumago is quite near Nagiso station and inexpensive if you have to use a cab. We had a strange experience. There was a bus outside the station, I asked the driver if it went to Tsumago and he said no. We took a cab and arrived at the same time as the bus ??? My Japanese is good enough for those kind of enquiries. After walking to Magome we found the bus service back to a station was somewhat lacking in frequency. It cost us about Y3500 to get back to the railway at Nakatsugawa. No big deal in the overall scheme of things but a little annoying considering we could have avoided it by better planning. I could not find anything definitive on bus services to plan properly. I hope you have better luck.

We'll shortly be staying at Magome so will start the walk from there. What's the best transport to return from Tsumago to Magome please?

Ther is a bus staion (small) ay the far end of tsumago as you would see it from the magome approach. it is actually not in the old town but just thru it and on the highway. several a day I think. Better still stay at one of the lovely inns in tsumago. this was the highlight of our trip. your luggage can be forwarded from magome on the bus and you can then bus out of tsumago to nagiso station, 10 mins

Just arrived in Matsumoto and will be staying 2 days in Magome.
Is there a recommended way to travel this route by bus or train, please?

By train along the valley and buses between the stations and towns:
http://www.japan-guide.com/e/e6079.html