Hi Fox,

re:
> Is it possible to set up a custom navigation for the viewports? Something like
> 3dsmax navigation (MMB=pan, MMB+alt=rotate, MMB+alt+ctrl=zoom)

Plain MMB drag is already pan in the default setup. There are some options for changing navigation under Options > View > Rotate/Pan/Zoom options, and then some additional ones in moi.ini which can be edited by Options > General > "Edit .ini file" button.

There's a new option in MoI v4 in moi.ini for setting rotate how you want, that's under:

[View]
<....>
AltMMBRotate=y

There isn't currently any option for doing zoom by MMB drag, I'll see about adding in an option for that for the next v4 beta though.

- Michael