It appears to have calculated the monthly and annual totals correctly at start up:
22/10/2014 09:24:54.380 : Rainthismonth from dayfile.txt: 81.9000015258789
22/10/2014 09:24:54.380 : Rainthisyear from dayfile.txt: 833.099853515625
And if use your dayfile.txt, the figure shows on the main screen correctly:
2014-10-22 17_05_30-Cumulus.png
The rain figures get updated each time a rain data packet is received, so I think the problem must be that your rain gauge is not transmitting. Is the console showing rain data? Did you leave Cumulus running long enough for a rain packet to be received?
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