I get the 0420 and 0430 at least once a week! I just live with turning it off with my code reader but will move the sensors eventually.
You're not alone - Mrs TB gets it when she uses TBE. I never have, she clearly is driving like tunnie.
I thought we moved the sensors on that one?
You tried. You failed 
Given you failed, I didn't even try
. As Gixer says, needs new sensors... ...but looking at trims, I think it may possibly need new injectors as well. Needless to say, no issues when I drive it...
Your lpg nozzels are still too big though, aren't they? Or did you sort that out?
I melted the replacements 
But its noticibly grumpy now until warmed, I believe you had this?
...still do to an extent, but it's not engine temp related. Build up of fuel trim at tick over I guess as it does eventually start to hunt after two or three minutes at idle.
The lpg map is a bit vague to map at low rpm, but I minimised mine by lowering the map parameters at tickover rpm levels. I presume its giving too much fuel at tickover, and being trimmed back and the cycle repeats.
My current Hanna injectors have no nozzels and do it all by duration. A bit of a pig to map as they are the complete opposite end if the map scale to the moto gas ones. The lambdas where not switching at all initially as it was way too rich working with the motogas map. But got there In the end.
Currently, there is a hunt that creeps in after 2/3 mins at idle, and it's set to switch back to petrol over 5.5k rpm. I'm sure these things could be tuned out though, if I could be arsed.
Yours however, needs smaller nozzels. No point changing anything until they're sorted, surely?