Hi all
The following may help in some situations, where fillet refuses to work.(V2)
Steps---> export part as *.SAT and reopen this as SAT.
For test ---> filletbu1.3dm fillet with "Radius 1" was not worked. Save this file as SAT and and try fillet,
new working with all options.
For test ---> filletbu2.3dm fillet with "Radius 2", option "const dist". was not worked. Save this file as SAT and and try fillet, new working.


File 5 has not worked with this steps, i was able to merge with one click but fillet destroyed geometry.

-regards