Alde propane failure - stuck gas valve - fixed!

Two days before our annual pilgrimage to Arizona in search of the sun, I discovered our Alde wasn't working on propane.  I checked all the posts I could find, but none of the solutions in the forum helped.  I could hear the clicking of the igniter and the blower was working as expected, but the propane never lit.  I checked that propane was getting to the unit, but I never smelt any propane in the exhaust.  I came to the conclusion that the gas valve wasn't opening, so with one day in hand I tore into the unit.  Here are the steps if this happens to you:
First problem on my TAB400 is that you cannot get the Alde access panel off, as part of the woodwork gets in the way.  An oscillating saw let me remove a section:

The access panel then comes off (after disconnecting the wiring) by removing 3 screws to reveal the innards.
To remove the gas valve, you need to undo the two gas line connectors arrowed in red, 6 electrical connectors, one rubber hose and 3 (if I remember correctly) screws:

You can then wiggle the gas valve out.  Next you need to remove the remaining gas line and rubber hood to give access to the screws beneath


Remove the 5 screws around the solenoid (2 of these require a security style Torx 15 driver) and lift off the solenoids and cover tubes to expose the pistons.  These pistons are supposed to lift up when the solenoids are energized to allow gas to flow.  One of mine was stuck in place but came loose with a little jiggling.
There is a third solenoid off to the side which can be similarly accessed - mine seemed fine.

Assembly is just the reverse of the steps above.  Make sure you get your gas connections tight!
So my Alde gas failure boiled down to a single stuck gas valve which freed up easily and everything works again.  Much cheaper than a replacement valve assembly that runs about $500!