This crate incorporates assembly code from the PMODE/W source distribution available from http://www.sid6581.net/pmodew/ – therefore I believe this crate must be distributed with the same restrictions as stated on that page:
"Due to the fact that PMODE/W is no longer supported it is now free for use in commercial and non-commercial applications, provided said applications are not themselves DOS extenders. To put it bluntly, don't go ripping off our DOS extender to make your own."