This is the plus/4 port of D64IT written by Errol Smith. This is a commodore program which can create D64 images of physical diskettes or write a disk image back to a physical disk. It uses KERNAL routines only so it's not fast but works with any kind of storages.
Fortunatelly it did not took a lot of effort to port it even the source was public.
The attached zip contains the source and the compiled binaries for plus/4, C64 and C128.
Update: there was several bugs in the plus/4 port (mostly memory-corruption), I've fixed them.