Reply flags for the message. These flags can be set as follows:
DMFL_NATIVERENDER
The source does not support rendering
for this object. A source should not set this flag unless it provides sufficient
information at the time of the drop for the target to perform the rendering
operation. The target must send DM_ENDCONVERSATION
to the source after carrying out the rendering operation or when it
elects not to do a native rendering.
DMFL_RENDERRETRY
The source supports rendering for the object but
does not support the selected rendering mechanism and format. The target
can try another mechanism and format by sending another DM_RENDER
message. If the target does not retry, it must send a DM_RENDERCOMPLETE
message to the source. This flag is set in conjunction with the DMFL_NATIVERENDER
flag.