Unless you've got a screen protector in place - which if installed incorrectly might reflect some of the issue.
Here is what I'd suggest you try to determine further: Hard Reset the device and see if "without any data on it" you notice the condition. If you do - then contact Palm for a possible replacement.
If you don't - then make a copy of your backup directory that contains all of your programs for the TX. Then delete the contents of the normal backup directory and hot sync this hard reset device. This will put your PIM data back on board but you'll have to go into that copy of your backup directory and add those programs back onto the device - one at a time until you find the one that causes the digitizer to not respond correctly.
Now to save some time - here are some programs that you might want to see if you have that normally affect digitizer issues: TealScript, Writeanywhere, Graffittianywhere, etc - those programs might not yet be designed for the TX. Or as I mentioned, it could be a screenprotector that isn't properly applied and is causing more pressure in the lower left corner?
