After many attempts at trying to accomplish this relatively simple task that I can do in ICEM Surf and Alias Surface, I have finally managed to achieve it in IDX.

Some observation points:

• When Cutting block surfaces, the Default Soft Parametric option is Reshape, even when the trim type is set to Trim not Face. i have found it is better to set this to Inactive as I would want to modify the trim converted patch rather than it parent root element.
• When OmniMatching, the default Soft Parametric mode is Adapt. This really stops four-sided matching as the matches are fighting each other. I set these to Inactive and it works fine. Note;  In ISD, I deactivate the match constraints, and in Alias, I delete the construction history of the align and keep the locator in place and adjust by tuning the control points. Alert mode allows me to do the same.
• the inner control points go a bit whacky when you match G1 or G2, but interestingly they sort themselves out when you go to modify the control points

• Still can't figure out how to snap an isometric curve - when using OmniCurve on a Surface to a vertex or OmniPoint