The latest update of Q-emuLator for Windows implements the extended system call to create a new directory in a QXL.WIN container or floppy disk (in addition to a Windows directory, where it was already available). It's also bundled with a more recent version 2.34 of the Toolkit 2 that includes the MAKE_DIR command.
The built-in debugger (accessed by pressing F11 while the emulated QL is running) has been updated and it now supports conditional breakpoints, complex expressions and text that is more readable on large displays.