ICON — Austin’s 3D-printing construction company — unveiled the model unit for its newest slate of homes at The Canyon Club in Spicewood. This time, the homes will be sold as part of a 1/4 fractional ownership program, which entitles buyers to 12 weeks of annual home usage and year-round club usage. ICON will build five homes at the lakeside resort community, which also has 20 traditionally built residences…