Logically, after defeating Azi Dhaka(something liddat...i forgot its name), one can continue to fight Vegnagun immediately without playing the pianos at all. Problem is, I defeated Azi Dhaka at the first barrier and still cannot continue on becoz the floating machines after the first barrier are still active!!! Moreover the pianos tt deactivate the floating machines do not work anymore! Can any1 solve this problem?

While I couldn't make out parts of your post, I think the solution to your problem is to hold down the action button (Circle) to jump over the security type machina that are still active.

to clarify my previous post...

Below is the path in the Farplane Abyss

Entrance --> keyboard 1 --> Barrier 1 --> Floating Machina 1 --> keyboard 2 --> Barrier 2 --> Floating Machina 2 --> keyboard 3 --> Barrier 3 --> Musical Pillars --> Vegnagun

Keyboard 1 deactivates Barrier 1 and Floating Machina 1
Keyboard 2 deactivates Barrier 2 and Floating Machina 2
Keyboard 3 deactivates Barrier 3

If not deactivated, a fight with Azi Dahaka will be triggered when Yuna reaches the barriers. The floating machinas, if not deactivated, will shoot at Yuna and push her back so that she cannot progress on.

This is what happened to me...I continued on to fight Azi Dahaka at Barrier 1 without playing Keyboard 1. After defeating it, I cannot get past Floating Machina 1 because it is still active, so I returned to try play Keyboard 1 but cannot because there are no options for me to choose to play the keyboard. In the end, I cannot progress anymore in the game. Any solutions to this?

Yeah, see my post above your last post.
You have to use the action button to jump over the Machina's attack.

Hope this helps

Yes, use circle and forward and make sure you're standing in the correct position. I had this exact same problem and when I figured out what was going on, I slapped my forehead like "duh!"

Originally posted by Agent0042
Yes, use circle and forward and make sure you're standing in the correct position. I had this exact same problem and when I figured out what was going on, I slapped my forehead like "duh!"

LOL. Same thing here. I thought, "whew! Glad nobody was watching that!"