[Windows Mobile Apps and Games] RoryB:
Depending on version of M2D, Action tab is just edit of the operator tab.

<OperatorWidget>
<Property name="IDOPERATORWG_START_POINT" id="0" value="0, 10" />
<Property name="IDOPERATORWG_Y_INTERVAL" id="1" value="10" />
<Property name="IDOPERATORWG_ROW" id="2" value="3" />
<Property name="IDOPERATORWG_COLUMN" id="3" value="3" />
<Property name="IDOPERATORWG_LASTPROP" id="4" value="0" />
<Property name="IDOPERATORWG_BTNSELECTED_IMGID" id="5" value="HH_LAUNCHER_BTN_OPR_SELECTED.png" />
<Property name="IDOPEARTORWG_BTNSELECTED_MASKIMG" id="6" value="HH_LAUNCHER_BTN_OPR_SELECTED_MASK.png" />
<Property name="IDOPERATORWG_BTNPRESSED_IMGID" id="7" value="HH_LAUNCHER_BTN_OPR_PRESS.png" />
<Property name="IDOPERATORWG_BTNPRESSED_MASKIMG" id="8" value="HH_LAUNCHER_BTN_OPR_PRESS_MASK.png" />
<Property name="IDOPERATORWG_BTN_IMGID" id="9" value="HH_LAUNCHER_BTN_OPR.png" />
<Property name="IDOPERATORWG_BTN_IMGMASK" id="10" value="HH_LAUNCHER_BTN_OPR_MASK.png" />
<Property name="IDOPERATORWG_BTNICON" id="11" value="68" />
<Property name="IDOPERATORWG_BTNTEXT_RECT" id="12" value="3, 90, 80, 77" />
</OperatorWidget>

and the registry

<wap-provisioningdoc>
<characteristic type="Registry">
<characteristic type="HKLM\Software\HTC\Manila2D\Operator">
<parm name="ServiceName" value="Action Screen" datatype="string" />
<parm name="SK1" value="Calendar" datatype="string" />
<parm name="SK1Cmd" value="" datatype="string" />
<parm name="Sk2" value="Settings" datatype="string" />
<parm name="SK2Cmd" value="" datatype="string" />
</characteristic>
<characteristic type="HKLM\Software\HTC\Manila2D\Operator\0">
<parm name="DispName" value="Messages" datatype="string" />
<parm name="IconPath" value="\Windows\OPERATOR_MESSAGES.png" datatype="string" />
<parm name="Path" value="\Windows\New SMS.lnk" datatype="string" />
</characteristic>
<characteristic type="HKLM\Software\HTC\Manila2D\Operator\1">
<parm name="DispName" value="Email" datatype="string" />
<parm name="IconPath" value="\Windows\OPERATOR_EMAIL.png" datatype="string" />
<parm name="Path" value="\Windows\New Mail.lnk" datatype="string" />
</characteristic>
<characteristic type="HKLM\Software\HTC\Manila2D\Operator\2">
<parm name="DispName" value="Alarm" datatype="string" />
<parm name="IconPath" value="\Windows\OPERATOR_ALARM.png" datatype="string" />
<parm name="Path" value="\Program Files\ageye\G-Alarm\GAlarm.exe" datatype="string" />
</characteristic>
<characteristic type="HKLM\Software\HTC\Manila2D\Operator\3">
<parm name="DispName" value="Appointment" datatype="string" />
<parm name="IconPath" value="\Windows\OPERATOR_CALENDAR.png" datatype="string" />
<parm name="Path" value="\Windows\New Appt.lnk" datatype="string" />
</characteristic>
<characteristic type="HKLM\Software\HTC\Manila2D\Operator\4">
<parm name="DispName" value="Task" datatype="string" />
<parm name="IconPath" value="\Windows\OPERATOR_TASKS.png" datatype="string" />
<parm name="Path" value="\Windows\New task.lnk" datatype="string" />
</characteristic>
<characteristic type="HKLM\Software\HTC\Manila2D\Operator\5">
<parm name="DispName" value="Note" datatype="string" />
<parm name="IconPath" value="\Windows\OPERATOR_NOTES.png" datatype="string" />
<parm name="Path" value="\Windows\New Note.lnk" datatype="string" />
</characteristic>
</characteristic>
</wap-provisioningdoc>

Of course, the exe and icon files must exist.