The date of the file creation depends entirely on the date setting on the computer the file was written. If that date was wrong, the files own date will also be wrong.

I have only seen two versions of the software, judging by the V - V1 and V2. I got V2 with the unit on a CD, with no clue as to the sub version. I downloaded a V2 marked as 4.12 from their site, then later one marked as 4.16. I also found a V1 which suggested to be more stable and perhaps free of the rainfall corruption.

I have the latest copy from the manufacturers site which is supposedly V2 4.16. This is 1.20 MB (1,261,568 bytes) and internally dated 12 April 2008, 23:21:42 - the same as yours. The 4.16 is now available at Fine Offset Eletronics Co.,LTD.

I also have a copy of the V1 I managed to find. This is 1.37 MB (1,437,696 bytes) and internally dated 07 January 2008, 23:35:24.

I no longer have a copy of what was supposed to be V2 4.12 against which to compare what is supposed to be the 4.16 I am currently using..

As you point out it is all very confusing due to the software writers poor control of his version numbers.

I have no opinion either way as to whether my rain gauge hardware is under or over reporting rainfall, though very obviously there is a problem with the software. The see very same (identical) gauge is used on more expensive systems than this one.