Yes, it was the "old" version of BigBox.exe 5.10. I've replaced the download now so if you reinstall the current 5.10 version over top the reports should go away. I tested it by installing the garbage on my own machine.
Like I said above, every time I compile Big Box I get different results, without changing even a tiny bit of the code. Half the time Big Box compiles and doesn't trip Kaspersky, the other half of the time it does. It's really quite ridiculous; I wouldn't expect the binary results of a compile to be different when the code doesn't change, but apparently it is somehow or other, and Kaspersky throws a fit.