payload help

[stocz2]

I have gone over the FAQ, and the help on the payload editor, but i can't seem to fix my problem.

I have downloaded all the payloads that i needed for my AC from http://www.fspassengers.com/?action=download&cat=All.

I have been flying for like the last 3 months now. All the payloads were working find. Then all the sudden when i load my passengers into
the planes. The nose of all the AC goes into the ground. All my smaller AC does this. I am a level 5c pilot only. This only happens in FS
passenger 2004. It doesn't happen when i just create a flight, with no passengers on board.
I have deleted all the AC from my FSPAss/payload file. Then redownload the payload from this forum site. And still have problems. I also
have been moving the center of gravity bar, forward, and backwards. Adjusted my seatings and cargo wt. But the front wheels get buried
into the ground after loading passengers an the AC. It's very hard for the AC to takeoff. And my landings are very bad, because of this now.
I also hit the estimate button, then it shows good CG. Then i think the problem is solved. So i go load the Passengers into the plane, then
there goes my nose, and wheels going into the ground.

What can i do to fix this? Please help.
stocz2