I have been following this post with interest, I have a Kabola OD4 which runs on the same principle as the Refleks, I have been have problems with the regulator and swapped it for the upgraded version, a TOBY DVR5, this has slight refinements over the old style regulator as it incorporates an oil shut off valve in the event of flame failure and an over-heating device (this is somewhat rudimentary and I suspect expensive to replace).
I have attached a picture of the old valve, with the thermo-coupled flame failure valve and along side that a 90C over boil valve and another picture showing the burner pot with the thermo-probe. The stove was built in 1998 and is rated at 4.6Kw. but it runs on the lowest setting. It also heats hot water. The new Toby regulator seems to burn more efficiently than the old one.