Go through and be sure the plot points are correct. Use the config program to import, then quit the game and open the imported save game with the Trilogy Save Editor, linked above. Extract it, then right-click it and choose 'install.'
The Legendary Edition doesn't support nearly as many mods. To get the Downloadable Content (install these before starting a new game): Mass Effect 2 Downloads, Hints & Cheats Nightsolo's Mass Effect 2 Downloads, Hints, & Cheats
