Nick_Pyner:
You will be better off forgetting about the LED, and addressing the real problem.You might find the following background notes useful
http://homepages.ihug.com.au/~npyner/Arduino/GUIDE_2BT.pdf
http://homepages.ihug.com.au/~npyner/Arduino/BT_2_WAY.ino
Your guide is a masterpiece!!!
I love this: "The big secret about Arduino to Android communication via Bluetooth is:
...
there is no big secret"
Thanks a lot!