Hi Flysail! welcome to the party!
that in and ex is a tad funny, we can import as metric, but as now, not export. SO : I select only my item(s), show only, then set my prefferences ( upper left on screen) to units> metric,mm then finally
yeah, I know, but I figure I'd rather go with this "glitch" and maintain good datas @ home than get some very bizaar parts which are unfixable from most sites!