The message count depends I think on where you look! The one on the emonCMS Input page comes from the sketch in the emonTx4, and it’s the number transmitted (every 9.96 s from memory). If there’s one in the ESP8266 page, it’s probably the same. “missed” and “missedprc” are, according to Trystan, missed messages - when I asked, he didn’t specify whether they are detected in emonHub or emonCMS nor say the criterea for including in the count, so I don’t really know what they signify. The statistics on the graph is the number of data points plotted v.s. the number expected over the period (so for my 24 hours it includes both ends - and I think it’s one too many, it should be 8641).
I only suggested the Variable Interval Timeseries feed as a diagnostic tool - it uses about double the memory of the fixed interval (because it stores Unix time for each data point) - in addition to the Variable Interval for data you will retain.