I'm away from my setup and won't be home till tonight late but am anxious to try your instructions and will get back to this forum as soon as I try it all out. I had found the link you posted and tried holding the key down as it said to do, but no go. I'm not sure if my Sonar 8 is updated or not, will find out. I so hope checking the controller as you said will work. This is driving me crazy.
After years of use, my brother moved from Sonar 8 to Logic and he's the one that has set up Sonar and everything for me. He's a guitar player and doesn't understand how important sustain is to a keyboard player. He told me to just do what he did on Sonar and go into piano roll and lengthen the notes.

The song I'm trying to record is 7 minutes long... can you imagine what it would take to do that in a song filled with elaborate keyboard parts? While he would never consider playing his guitar dry, he doesn't understand the essential need for the nuance of sustain. So, he will be no help on this. I say this so it will explain why I know so little about the set up myself. But for this sustain problem everything is gliding beautifully.
I'll be back as soon as I work the adjustments you mentioned to let you know if it worked.
Thanks lots... and lots.