Yeah there is a 4mb limit for attachments on posts lol
Ok looking at the log I do see 2 exes that are hitting that folder.
TSVNCache.exe
and
Dropbox.exe
Which I am wondering if dropbox is replacing the files from the ones from online storage if they are on there. Reason why is when you copy and paste the files from the computer over and they stay it is because the last accessed date or one of the other dates gets updated with the current time. Drop box sees that newer time and it looks newer than the ones online. But when you do a update the times are that of when the file was first made, making the files look older to dropbox which it would then download the ones from onlie replacing them because it thinks they are newer.
At least thats what it looks like lol otherwise dropbox shouldnt be touching that folder.
However I am also looking at the logs and I see other things happening as well.
I see msiexec.exe and Explorer.EXE also hitting some of the files. Right now I filtered out most of everything and only looking at what is happening with PositionMgr.exe.
Here we see the msiexec.exe reading the file
12:38:55.7766002 PM   MSIEXEC.EXE   7260   QueryStandardInformationFile   D:\Data\UA\PositionMgr.exe   SUCCESS   AllocationSize: 9,248,768, EndOfFile: 9,245,184, NumberOfLinks: 1, DeletePending: False, Directory: False
Then right after that it writes the file to there, I see TSVNCache.exe and Dropbox.exe accessing the file, then once they are done accessing it I see the msiexec.exe qurey the file again and this time it is a totally different size
12:46:09.8468666 PM   MSIEXEC.EXE   6116   QueryStandardInformationFile   D:\Data\UA3\PositionMgr.exe   SUCCESS   AllocationSize: 9,265,152, EndOfFile: 9,262,080, NumberOfLinks: 1, DeletePending: False, Directory: False
At which point I see msexec.exe and explorer.exe both write that file.
12:46:27.2249471 PM   msiexec.exe   1232   WriteFile   D:\Data\UA3\PositionMgr.exe   SUCCESS   Offset: 9,240,576, Length: 21,504, Priority: Normal
12:46:28.0024499 PM   Explorer.EXE   3484   WriteFile   D:\Data\UA3\PositionMgr.exe   SUCCESS   Offset: 8,388,608, Length: 876,544, I/O Flags: Non-cached, Paging I/O, Synchronous Paging I/O, Priority: Normal
12:46:28.0057759 PM   Explorer.EXE   3484   SetEndOfFileInformationFile   D:\Data\UA3\PositionMgr.exe   SUCCESS   EndOfFile: 9,262,080
So what I would do is get dropbox and that other exe to leave that folder alone and see if that does the trick. 

Shane