AFAIK, there is nothing in the Pegasus Mail configuration that should affect drag & drop. Neither would any of it registry entries. Those only keep track of the location of the last run instance and provide the necessary entries so that Pegasus Mail can set as the default email program.
I don't know what could be causing your drag & drop problem. Are you dragging from a file explorer and dropping onto the attachment pane?
AFAIK, there is nothing in the Pegasus Mail configuration that should affect drag & drop. Neither would any of it registry entries. Those only keep track of the location of the last run instance and provide the necessary entries so that Pegasus Mail can set as the default email program.
I don't know what could be causing your drag & drop problem. Are you dragging from a file explorer and dropping onto the attachment pane?