i know when i hook mine up, and this sometime happen i check the alligator clips on the connectivity kit. they may look like there connected, but not. when you turn connectivity kit on does the Led's come on(on connectivity kit? ur photo doesnt look like LED'S are on).
if they do check clips on connectivity kit. if they dont, try different molex. if you have multi meter, you can see if there is voltage by touching black lead to "GND PAD", and red lead to "3.3" pad.
solderless add on (7)- yes this will work for the 7 series drive. ive enclosed a pic of mine. this is what your talking bout right(see pic below).
if it is heres the tutorial:
http://www.tiaowiki.com/w/Xbox_360_Lite_On_DVD_Key_Dumping_-_TIAO%27s_Serial_Key_Extractor
also encolsed two pics. before & after (adjusted clips on connectivity kit while kit is on til blue light comes on) also notice the LED'S on the connectivity kit.