One of the cool things about new revs is that, it doesn't matter how long you've used the software, you get bumped out of the safe and familiar, into unknown territory. We all become newbies again. It can be quite disconcerting, IMO, depending on how much you valued your safe and familiar ground, the one where you were confident, competent and had most of the answers. It's hard to leave that but I'm enjoying the progress the software is making.
: If the mouse is positioned to cause the one-by-one to highlight (preselect ON, : color turns from red to cyan on my system); (1) the highlight changes, : (2) you "lock in" one-by-one mode and can (holding ) add or : remove curve segments. : You're right about the selection process being key to everything in those functions that have gone object/action.
: If the original one-by-one isn't highlighted when is pressed it dumps : you out of one-by-one mode and into one of the "loop" modes which can be : cycled through with rmb. : Here's the only way I could get a composite curve created with 'Edit>Copy':
1) Preselect (highlights cyan), then select (highlights red) one curve segment. (More than one selected and 'Copy' stays greyed out.)
2) Pick menus 'Edit>Copy', selected segment shows thick red with t=0, chain, t=0 on arrows.
3) With shift key held down, pick next segment. End point (t=0) jumps to end of second segment.
4) Continue until all segments picked. End point of approximate composite curve keeps jumping to end of new segment.
5) Click the green check to finish.
If there's another way to do this, I'd like to know.
: According to Help > Fundamentals > Working with the Model > Selection >
: ...Chains.... you can initiate another one-by-one by pressing and : picking an edge. I couldn't get this to work, but maybe it's only available : while some other function (other than copy) is active (?). : This may only apply to surface/solid edge chains, not curve chains.