full manual could mean no automation, so focussing and setting of shutter speed and aperture all have to be done manually. The FZ10/FZ20 fails the requirement then ;p
But they do have sufficient manual features for the users to have control over the camera. I'm not too sure about manual focus though. Generally, it's not as easy to focus using a EVF compared to a real TTL viewfinder.
I have the FZ10 and it does not have an AE lock. Not too sure for FZ20.
Of course, when you press the shutter halfway, you are locking BOTH Exposure and Focus. If I understand you correctly, you are asking for a dedicated AE lock seperate from focus lock. It was my same question in DPreview, and this was the rply I got, and I think this is a good work around...
"Here's how I do it.
Set the camera to Aperture Priority exposure and Manual Focus.
Point at what you want to focus on and briefly pull down the focus switch (I use the thumb on my left hand as it cradles the camera) - this temporarily auto-focusses. When it locks on, release your thumb and the switch pops back to the middle.
Point at what you want to meter on and half-press the shutter, locking the exposure. Keep the shutter half pressed, re-compose and shoot.
You can also use Shutter Priority but I find the small number of f stops limiting in this mode.