Thanks for all your feedbacks :)
For my specific problem (because there's sadly never one solution for each transition problem) I may have found a workaround !
I add motion 1, add a transform key at the end
I add motion 2, add a transition key at the beginning
I add the desired transition from motion 1 to 2 and select "create transition clip" (just discovered this), right clicking on motion 2.
I "reset pivot" on this transition clip and then I tweak this transition with some transform key where needed.

The end steps allow me to keep the transition in place, removing this slide effect, I just have to add transform keys if the avatar must move during this transition.



I never figured how to make this working. And I didn't understand why it could be better to link a dummy prop instead of just turning the avatar directly. I'll try again.

sonic7 (11/12/2018)

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@ DrNemesis ... I didn't realize Align Motion was broken ... well that explains why the results have been so 'hit and miss'. I'll add my vote right now ..... thanks. :)

 Oh ! As a beginner I didn't know it was broken, I thought it was normal behaviour. I can not wait to see what it looks like when not broken.

Neal  >>> " ... you have to add a dummy prop, select character, link to the dummy, select dummy, Turn dummy to correct orientation, select character and play animation to see if it was correct, ... " <<<
Yes .... I've been playing around with that approach myself - with, unfortunately, limited results.

@ DrNemesis ... I didn't realize Align Motion was broken ... well that explains why the results have been so 'hit and miss'. I'll add my vote right now ..... thanks. :)


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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time! :(  - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1

Align motion is currently broken in 7.23.
Works in 7.21 and 7.22

In 7.23 moving the hip bone of an animation that has root bone rotation will have weird results.
This simple problem breaks several functions in Iclone, one of which is clip alignment.
I filed a bug a few weeks back.

https://www.reallusion.com/FeedBackTracker/Issue/Moving-a-character-s-root-bone-now-results-in-broken-animation

Edit:

sonic7 (11/12/2018)

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Yes it does seem very strange that the 'solution' of quite a few iCloners is to NOT show the feet (as a work-a-round) - yet they're avoiding showing animated feet from an 'animation' software lol ....

Interestingly (maybe) this isn't just an Icloner thing. Walks can be among the more annoying animations to depict properly, partly because of foot issues so just not showing them saves work. Even in professional environments with more resources and using more expensive software you'll find people avoiding this unless it's specifically needed.

After working in iclone for about a year now on and off I've been working my way through my project for scene setting/lighting etc, with a tone of video tutorials from the great folk here, I am now on the character animations part which as you all say is a pain in the BUTT, to string a couple of convincing movements together is not easy, you end with one motion going one way and a new one going another, you can not just rotate him.......like you would expect to be able to do, you have to add a dummy prop, select character, link to the dummy, select dummy, Turn dummy to correct orientation, select character and play animation to see if it was correct, if not go back and tweak again, if good then hide dummy,....all this for an "animation" software!
Also, I find the only convincing animations including a simple walk is the mocap ones which you have to buy, the walk ones that come with Iclone I find not to be very good, on one I see a strange foot flick just on one leg?
The Mix Moves are a good idea and work well but we need more with more variations like walk then stop then walk backwards, Mix Move fighting to seamlessly create combat situations plus lot's more.
Thanks Sonic7 and others for the tips, I'll give it a try but it does show that this needs looking at for IC.
N. 

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View my latest Iclone project THEY ARE HERE Renegades versus the overlords 

Yes it does seem very strange that the 'solution' of quite a few iCloners is to NOT show the feet (as a work-a-round) - yet they're avoiding showing animated feet from an 'animation' software lol ....
Anyway - we need to stay 'positive' and 'creative' ....

I get 'mixed results' from this method. Some 'close' to good, but others with a tad of gyration ....

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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time! :(  - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1

Walvince, you're not alone at all, as Sonic and Mike said,  we all found these problems but the solution?....even on the videos of demonstrations on marketplace I see foot sliding and so...


     

I don't think they will fix it for the same reasons I think if you find a tutorial that Rampa did three years ago it will probably work exactly the same -- RL is LOATHE to change anything that affects stuff retroactively.

In some ways it's a Good Thing -- you can, with pretty much good confidence, be assured that things you have always done can always BE done.  But in other ways, if a core thing is really screwed up and should be fundamentally rewritten, it means it cannot.  The best that can be done is to add some kind of kludge on top of it (which won't work well, or at all at times).

Where they make major breaks nearly always come in things like avatars, where they have "generations" -- the old generation still works exactly the same way, but the new stuff can only work in the new way.  (I would argue that if they can do this they really ought to fix major issues like this pivot point and say "hey, it's much better NOW" but that's just me).  If they were to rewrite things like the pivot issue it would almost surely be in something like version 8 (which they should call something other than iClone -- again, that's just me, but I'd start from scratch with a new name and a 1.0 version that did a lot of things right but didn't keep all the old baggage).

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley

Not sure if I'm on to something here, or whether it's a fluke, but try this:
As soon as you've set the second 'Transform Key', right click on each clip and click 'Reset Pivot' (do that on BOTH clips).
Now BEFORE proceeding on to the 'Rotating clip 2' part, make sure your cursor line is right on top of clip 2's Keyframe (making the key frame 'active' - talking of the first frame of clip 2), and NOW go ahead and adjust the rotation - see if that works for you ...

To clarify:
* Set a 'Transform Key' at the very end (last frame) of motion 1
* Add a 2nd motion, remove it's 'Transition' and 'butt' it right up against the end of clip 1
* Set a 'Transform Key' at the very start (first frame) of clip 2
* Right click on each clip and click 'Reset Pivot'
* Click onto clip 2's Keyframe (making it active)
* Align clip 2's rotation to match the orientation of clip 1
* Then select (on clip 2), 'ALIGN > ROOT'
* Slide clip 1's 'Transform Key' several frames to the left and THEN left-slide-out clip 2's transition region 'up to' (but 1 frame before reaching) clip 1's end transform key.
(so the 'transition' region spans between the 2 created key frames).

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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time! :(  - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1

Kelleytoons glad to see I'm not the only one thinking this way. I am totally new to animation softwares but it seems obvious that the pivot should never behave this way.

Why do you think RL will never fix it ? It seems to be a so major problem to me.

I saw somewhere that Rampa had done a tutorial about aligning the pivot but I can't find it. It was 3 years ago so it's maybe no longer to take in consideration.

Yeah - I've seen that effect for sure .....
I'm playing around with this myself now that you've posted ....
We'll see whether 'You', 'Me' or 'Some other member' totally nails it....
Like I say, I'm keen like you to get this totally right ......  :)

Edit: .... Yeah well summed up Mike .... makes a lot of sense what you say .....


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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time! :(  - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1