Filleted edge means rounded edge. So, you'd need to work with the rounded cylinder and cube in Bryce to get some of the stuff I did. I congratulate you on the base, but it's not the same. The top of the octagonal part is rounded, as well as the middle and the bottom. Before I got Rhino, I also found modelling in Bryce easier, but now, as I said, I completely forgot it. And it's different stuff anyway. The only Booleaning I did in Rhino was to create the slot on the top.

-- erlik