yhap2003,
Not knowing your original firmware is going to be tough.
What has happened is the firmware you upgraded to is not compatible with your player which is why it is not working. To fix it you need to find the right firmware for you player.
I suggest you download as many firmware as you can find and using s1res (you will find it in the Download\Tools section) open them and look at the images they contain for menus, backgrounds, boot screens etc. Ones you find that look the same put aside ones that look different delete.
Next you are going to have to try the various firmware you have that match image wise, but there is a good chance things are going to get worse before they get better as your player may end up not being recognised by your PC in which case you will have to follow the dead player recovery process.
I have outlined how I have done this in a previous post along with some links to firmware that may be helpful.
http://www.mympxplayer.com/viewtopic...r=asc&&start=0
Sorry but there is not a lot more advise I can give you, Good luck.