Export to MCNP format fails

My attempt to export a FLUKA geometry into MCNP format ending with several errors.
Examining the converted file, I noticed that the MCNP region’s block is separated from the surface/body’s block by two blank lines (instead of one). Furthermore, the material block is not separated from the surface body block. These errors can be easily fixed by hand.
The main problem is that all the surface/bodies have lost their numerical labels, causing many errors in the MCNP pre-processing. In these conditions, the body (surfaces) are uncorrelated with their declaration into the upper region’s block.
The problem is present also in a simple export attempt generated using the FLAIR template for a FLUKA basic input.
May I missed something?
Thank in advance

Thanks Nunzio for reporting,

Indeed there is a problem with the released version. For the moment, you can perform the conversion wif you enable the development features like
flair -d
This problem will be fixed in the next flair released

It works.
Thank you.