Here are the changes, you can ask for more detail in the www.dvbdream.org forums

  CHANGES

  v2.0 (17.08.2012 - DD 2.0)
	  DDMODAPI_SHOW_SCHEDULER = $00100071; // displays the scheduler dialog
	  DDMODAPI_STOP_DEVICE  = $00100072; // stops device
	  DDMODAPI_START_DEVICE  = $00100073; // starts device	
	* DVB-C Modulation constants changed
	* Added pilot and roll-off constants
	* TEnvironment structure has been updated. EPG related environment values have been added to use with dvbstr functions.
	* TTransponderInfo has been updated to carry bandwidth, pilot and roll off information
	* TChlChannel has been updated to carry tuner type, bandwidth, pilot and roll off information

  v1.9 (04.10.2011 - DD 1.5g)
	DDMODAPI_GET_EPG_CURRENT2
	DDMODAPI_GET_EPG_FOLLOWING2
	DDMODAPI_GET_REC_STATS
	DDMODAPI_SET_STREAM_CB
	DDMODAPI_FREE_STREAM_CB
	DDMODAPI_RESET_DIRECTSHOW
	DDMODAPI_TUNE_DIALOG
	DDMODAPI_TUNE_DIALOG2
	* DDMODAPI_GET_DEVICE_INFO  and OnInit() now can  be used to 
    	get the BDA tuner filter name, 
	look at the following file for more information
	"getting bda tuner filter name from DVB Dream.txt"


  v1.8 (05.08.2010 - DD 1.5d)	
	  DDMODAPI_GET_TUNER 
	  DDMODAPI_SAVE_SNAPSHOT 
	  DDMODAPI_GET_VIEWABLE
	  DDMODAPI_SET_VIEWABLE 
	  DDMODAPI_CLEAR_VIEWABLE 
	

  v1.7 (....)
	  DDMODAPI_PIP_OPEN
	  DDMODAPI_PIP_CLOSE
	  DDMODAPI_PIP_SHOW 
	  DDMODAPI_PIP_HIDE 
	  DDMODAPI_PIP_REC_START
	  DDMODAPI_PIP_REC_STOP
	  DDMODAPI_PIP_GET_DATA
	  DDMODAPI_PIP_SET_DATA
	  DDMODAPI_GET_PIPCHLS 
	  DDMODAPI_SET_AUDIO_PID 
	  DDMODAPI_SET_ASPECT_RATIO 
	  DDMODAPI_CHL_API
	  DDMODAPI_SELECT_CHANNEL_BY_CHID
	  DDMODAPI_START_PIP_RECORD
	  DDMODAPI_STOP_PIP_RECORD
	  DDMODAPI_START_RECORD_ALL
	  DDMODAPI_STOP_RECORD_ALL
	  DDMODAPI_ADD_PIP_RECORD
	  DDMODAPI_MINIMIZE
	  DDMODAPI_QUIT_AFTER_RECORD
	  DDMODAPI_SHUTDOWN_AFTER_RECORD
	  DDMODAPI_GET_DATA
	  DDMODAPI_SET_DATA
	  DDMODAPI_ADD_RECORD
	  DDMODAPI_GET_INTERFACE_LIST
	  DDMODAPI_SWITCH_DEVICE
	  DDMODAPI_GET_TP_LIST
	  DDMODAPI_GET_SAT_LIST
	  DDMODAPI_GET_SETTINGS_POINTER
	  DDMODAPI_STOPFILE
	  DDMODAPI_SEEKFILE
	  DDMODAPI_GET_KEYS_POINTER
	  DDMODAPI_GET_SELECTED_CHID
	  DDMODAPI_START_EPG2
	  DDMODAPI_STOP_EPG2 
	  DDMODAPI_SET_RECFILENAME
	  DDMODAPI_SET_RECFORMAT


  v1.6 (25.09.2006 - DD 1.2)	

  v1.5 (22.05.2006 - DD 1.0)
   	- Architectural changes
   	
  v1.4.7 (incoming version..)
	- added following events
      DDEVENT_ON_START_RENDERLESSMODE
      DDEVENT_ON_STOP_RENDERLESSMODE
      TVideoInfo structure changed

  v1.4.6 (29.06.2005 - DD 0.8.8)
    - Callback function type changed
    - added following messages
        DDMODAPI_RENDERLESS_MODE
        DDMODAPI_CHL_GET_POINTER
        DDMODAPI_CHL_SAVE
        DDMODAPI_CHL_LOAD
        DDMODAPI_CHL_API
        DDMODAPI_SELECT_CHANNEL_BY_CHID
    - added CHL structures  (CHL = new channel list format)



  v1.4.5 (30.12.2004 - DD 0.8.7b)
   - added following events
      DDEVENT_ON_WINDOW_NOTIFICATION
   - added following structures
      TWndMessage

  v1.4.4 (18.12.2004 - DD 0.8.7a)
   - added following events
       DDEVENT_ON_DEVICE_RESTART
   - added following messages
        DDMODAPI_GET_DISPLAY_HANDLE
        DDMODAPI_GET_DISPLAY_OWNER_HANDLE
        DDMODAPI_GET_DEVICE_INFO
        DDMODAPI_SET_REMOTE_CALLBACK
     DDMODAPI_GET_FILE_INFO
    DDMODAPI_PLAYFILE
    DDMODAPI_PAUSEFILE
    DDMODAPI_GET_RECORD_PATH
    DDMODAPI_OSD_CREATE_SURFACE
    DDMODAPI_OSD_SHOW_SURFACE
    DDMODAPI_OSD_HIDE_SURFACE
    DDMODAPI_OSD_GET_SURFACE_BITMAP
    DDMODAPI_OSD_REPAINT_SURFACE
    DDMODAPI_OSD_SET_TRANSPARENCY
    DDMODAPI_OSD_DESTROY_SURFACE
    DDMODAPI_OSD_GET_WINDOW_HANDLE
    DDMODAPI_GET_RECORDING_STATUS
   - added following RC key constants
      RMT_PLAY, RMT_FORWARD, RMT_REWIND, RMT_PAUSE, RMT_SCHEDULER
     RMT_MENU, RMT_RED, RMT_GREEN, RMT_YELLOW, RMT_BLUE, RMT_RADIO, RMT_RECORDLIST
   - added device type, tuner type and transparency mode constants
   - added TOSDSurface, TSetRemoteCallbackParams, TDeviceInfo structs
   - added dwOSDTimeOut into TEnvironent

  v1.4.3
   - added following messages
     DDMODAPI_SET_DISPLAY_MODE
     DDMODAPI_GET_DISPLAY_MODE
   - added displaymode constants

  v1.4.2
   - changed TEnvironment, now using only one OSD bitmap
   - added OSD width, height constants
   - added following messages
        DDMODAPI_SET_OSD_COLORKEY,
        DDMODAPI_QUIT,
        DDMODAPI_POWEROFF,
        DDMODAPI_GET_TRANSPONDER_INFO,
        DDMODAPI_GET_DD_VERSION,
        DDMODAPI_GET_API_VERSION

  v1.4.1
   - added OSD commands
   - some changes on EPG commands

  v1.4
  - added DDMODAPI_ADD_LOG
  - changed TEPGInfo structure
  - added MODTYPE_CHLIST_TOOL
  - added MODULE_API_CURRENT version-constant
  v1.3
  - added DDMODAPI_REFRESH_CHLIST
  v1.2
  - added dwSize to most of structures          (23.07.2004)
  - added bSchedulerInstalled to TEnvironment   (23.07.2004)