Hi all again!  Is there any way to add a new unit system option besides those default IPS, MMGS, CGS and MKS?

For practical engineering around the Metric World, a Millimetres Kilogram Seconds (MMKS?) would be a most needed addition.

Now, at least I don't know other means than opt Custom units and switch grams to kilograms.  No problem if I use my own templates (beginning from scratch), it's done years ago and OK since.  But, feels a bit annoying when working with existing/old/somehing-outta-there/misc files.  To neglect means more mess.

Non-SI of course but common engineering pracice, yes.  I suppose I'm not the only one missing this feature.