The ActiveX part of MysterX is gone. The `ffi/com' re-imeplemtnation
provides only core COM support.
The "mysssink" DLL is still needed, and its source is still
in the tree, but it is downloaded in the same way as other
pre-built DLLs. The DLL no longer needs to be registered with
regsvr32.
The prohbition against `handle-evt' on `handle-evt' is as
document and as originally intended. I'm not sure why it
was allowed.
Existing programs that use `handle-evt' incorrectly
can break. I found and fixed one incorrect use and one
questionable use in the Racket tree (which is a small
minority of the uses of `handle-evt' in the tree).
