I tried unsuccessfully, several times, to update the flarm portables in our club towplanes with the file downloaded from the Flarm site.

When you download the file directly from Flarms site, the file name is powerflarm_6_06_8249.fw and the flarm does not recognize it on boot up.

I am told that changing the filename to powerflarm_6.06_8249.fw fixes the problem.

In short replace 6_06 with 6.06 in the filename.

It does not seem to affect every unit, but it has caused issues with some Cores and some Portables that I have heard of.