George,

I did find this in the help file:

cdlOFNAllowMultiselect &H200
Specifies that the File Namelist box allows multiple selections.
The user can select more than one file atrun time by pressing the SHIFT key and using the UP ARROW and DOWN ARROW keys to select the desired files. When this is done, the FileName property returns a string containing the names of all selected files. The names in the string are delimited by spaces.

How did you come up with 0x200 for &H200?