Is that the House of Fallen Trees? I had lighting issues with that particular lot. You could try the lot lighting cheat which fixed it for me.
From the Prima Guide
"setLotLightingFile [filename]: Change lighting by choosing an alternative lighting file. The original can be found in C:\Program Files\EA GAMES\The Sims 2 Nightlife\TSData\Res\Lights. Place your new lighting file in this folder and use the cheat to specify the file name for the open lot. To restore the lot back to the original lighting settings, input *setLotLightingFile clear*."