For many functions of DMEX shortcuts are defined by default. The shortcuts can be changed in the configuration dialog.
The defaulkt shortcuts are shown in the following table.

This means if you press Ctrl-F6 in any explorer window you directly open the Change to... menu or by pressing Ctrl-F5 you copy the selected files to the aligned explorer window (if any).

Default shortcuts in DMEX

Key   Function if pressed together with Ctrl  Function if pressed together with Ctrl+Shift 
Function keys      
F1  Show DMEX Menu  Show DMEX Menu Shortcuts 
F2  Rename files    
F4  Close all explorer windows    
F5  Copy selected files  Move selected files 
F6  Show "Change to..." menu  Show "Run..." menu 
F7  Create new directory  Clean directory 
F8    Move files one level up 
F9  Show "Change Drive" menu  Synchronize directories 
F10  Show directory size  Show free disk space 
F11  Arrange two horizontal  Arrange two vertical 
F12  Create versioned files  Restore versioned files 
Other keys      
  Copy selected filenames 
  Paste clipboard content to file 
Select all files with same names  Select all files with same extension 
Tab  Focus aligned explorer   
Minimize window   
PageUp  Change to parent directory   
Pos1  Change to root directory