Hi Michael and Mark and all,

Ok now !
Thank you very much for your explanations :-D

What was confusing for me was my computing reflexes : when I typed numbers I validated with [Enter] waiting the object understand the typing and draw itself consequently.
Well, I waited the automatic drawing... And now I understand I can continue to wait if I have time enough ! ;-)

The same for re-sizing objects : after selecting the object to re-size I typed measurements within the "XYZ" boxe and after [Enter] I thought the object could redraw itself... Astonishing, no ? ;o)

For all newbies as me, maybe it could be cool to explain exactly the sequence needed for Distance and angle tools as for the properties panel ; for instance for a line :

Distance & angle :
1) after selecting the line tool clic the first point of the object to draw the beginning of the line
2) then directly on keyboard type a number and do [tabulation] to let the system understand that you typed something or clic within the distance box and type your number on pad then clic OK button.
3) with your mouse in the drawing window choose the direction you want for your fixed measured line and clic to fix and draw it.
3bis) you can do the same within the angle box to constrain some angle directions before your last drawing clic.

Properties panel (to change dimension of an object after drawing) :
1) clic on the object you want to change measurement and clic dirdctly on the text showing the size on the top right corner of the MoI window.
2) clic within the box you want to change, type new number and [tab] or [Enter] to validate.

There a small flv video file showing the process helping to understand it is not needed to complicate the life as I have done ;-) :
http://www.adalius.fr/media/20120619-4MoI-forum/MoIDistanceAngleProperties.flv
(download the link to your disk to open it with VLC for instance)

Hoping this will help a bit some newbies to keep it simple !
Best Regards,