Recovering methanol is definitely worth doing. I'm getting 40% return from the glycerin alone. I havn't attempted recovery from my diesel yet.
This is how I do it: A metal paint bucket is filled to about 2/3 with glyc., it goes on a hotplate which is controlled by a thermostat set to about 60C.
Vapour goes up the tube, through condenser, into collecting drum.
Condenser is an adaption of something I've seen on the net some years back, can't remember where. Just can't find it again.
As you can see, it's a plastic drainpipe with 2 tees and 4 endcaps.
The copper pipe inside the drainpipe has been crimped with locking pliers.
The crimps are alternate i.e. north-south, east-west, all the way along the pipe.
The glyc sits there for about 6 hours(timer) and don't forget to turn on the water.