Hi Art,

re:
> but the fact I cannot even chamfer something so simple makes my confidence going
> forward shaky for the main design.

Well if it makes you feel any better, shapes that have surfaces meeting at shallow angles and containing vertices with 5 edges coming out from a single shared vertex are pretty difficult cases for fillet/chamfer, not really a simple case for them at all.

What would make it simpler would be to have lower number of surfaces - areas where you currently have blocky pieces meeting at a shallow angle should be larger smooth surfaces and that will help reduce higher vertex valence counts as well.

- Michael