Well I had to fire up my old copy of Hexagon 2.5, just to try it out.  I had to write down the location of some of the tools, because you're right, they are in strange places.  What the heck is vertex modelling anyway, and why are all the edge tools in there?  Anyway, once I got the tools locations down pat, I gave it a real go.  Seven times.  Faced lots of problems right away.  For one thing, almost nothing is assigned to a hotkey by default, so unless you went and assigned them manually, you gotta go digging through flyout icons to engage some of the necessary operations.  I couldn't find a quick way to tessellate the necessary edges to start out with.  When you use the Quad Tessellation tool, it either makes too few, or too many cuts.  So you have to make one tessellation with the Quad Tessellate in face mode, then switch to edge mode, and make a chamfer on those edges, and so on.  So it was a lot of steps there.  Also, there's NO easy way to select the faces, once you "extrude" them inside of the cube.  So, once you average weld them together, you're left still with faces that need to be deleted at the end.  I got a result, but it took almost 5 minutes.  I think even if I was an expert with the software, it couldn't be done in less than a minute.  I'd be surprised.

Oh, and I should also mention, there's no Similar Select in Hexagon, so that slowed me down a lot.  Especially at the part where you have to delete all the corner faces.  Does Silo have this?  I thought maybe I could select all the faces in a cross shape on each side of the cube, then just invert that selection to get all the corner faces, but Hex gave me problems even with that kind of selection, because it won't let me make face loop selections in two different directions for some reason.  Making certain types of selections is definitely a slower process in Hex than I expected.

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Tools :  3dsmax 2015, Daz Studio 4.6, PoserPro 2012, Blender v2.74

System: Pentium QuadCore i7, under Win 8, GeForce GTX 780 / 2GB GPU.