Ok, open Notepad and paste the following VBScript into it:
set wShell=wscript.createobject("wscript.shell")
wShell.sendkeys "^{ESC}"
Save it with the extension as .vbs (NOT .txt)
Create a new shortcut in your Dock and make it a shortcut to the VBS file.
This shortcut should now open the start menu! It did for me!