Hasta La Motion!

there are almost 5 thread about topic (little variation) few are little helpful., but in true context, problem remains and exist, so i finally decided to ask and get this solved for myself and others here…

tools using (3dsmax / mental ray and nuke)

BIGGEST QUESTION:
1- is it possible to have ID’s pass as integer values but "antialiased" from 3d app
2- is it possible to convert RGB image to Interger values, in nuke.

CURRENT WORKFLOW:
in 3dsmax:
when rendering EXR, it gave me option to embed id’s inside exr, when i see details, it is called "mono" for encoding option, this is where HUGO gizmo works, except anti-aliasing option doesn’t help much..

if i enable render elements separately, then it created rgb image. it seems best "anti aliased" but HUGO gizmo doesn’t work here.
how can i convert my id’s (rgb) image to INTEGER values. inside nuke??