In short:
Top right:Soft Reset Enable/Disable: Turn on Soft reset for ALL games
Passme Mode: Click this to boot your slot-2 flashcard
GBA Mode: Click this to boot your GBA game or GBA flashcard
Power Off: Turn your DS off
Adjust Light: Set brightness of your screens
Back: Go back to TTDS main menu
Select a game by pushing the D-Pad up or down and press then "SELECT" (or just click the medkit icon shown under the size of the game) gives you an option menu for that game only:
first option 
shows nothing just an option to enable/disable:
This will show a disc icon with a green arrow under the game name in the game menu, seems it means cheat code support ?
Soft Reset enable/disable:This will show a red powerbutton under the game name, indicating soft reset is on for that game
Cheat Code enable/disable:This will show an orange icon with a key under the game name, indicating cheats or turned on for this game
Main menu:When you see a send/recieve DS icon it means Game has Download play
It seems the TTDS recognizes games with Download play
Cheat codes:You can use the R4 usrcheat.DAT, just place it in the TTMENU folder
Press the medkit icon next to the game and enable cheats, now press the cheat tab on top of the screen, if the game has cheats in the database, you should be able to select them.
Using XML files didn't work, seems you can only use the usrcheat.dat from R4 (not the cheat.dat)
Sow,
This was a quick tutorial
