Most applications do not need the Windows "born-on" date in order to work very well. Geez, all Unix applications seem to get along fine without it...

This Windows file system parameter does have its uses. However, my recommendation would be to not use it unless necessary. That means only do it if, a) if the standard Perl multi-platform file tests do not provide adequate information and b)you are willing to write O/S specific code. In the OP's case, probably the -M file test is just fine. The "born-on" date requires a call to a Windows specific API.