It's not really nice...
How to solve?
You could add a class to the group and set its height
group settings
ui-template for CSS
EDIT
Correct spelling of height is entirely optional 
Don't work and I don't understand where where am I wrong ...
Works for me.
I'm afraid I cannot help you if you dont show what you did.
The class name must be update in the page and in every groups?
Only the short group. Note however, if the longer group is being made bigger due to its internal widgets forcing it to be bigger, it might not work!
Try setting the class name on the 2 groups you are trying to align & set the CSS value to 600px !important - do they both size up to 600px?
Try also inspecting the elements in your devtools to see why it isnt applied.
I reduced the size of labels and now the group are almost alignment (without class) and for now I'm ok.
Thanks for the help...
EDIT: I added two gauge and now I have the groups out of alignment again ...
Is possible to have a class that allow to set the widget gap for every group?
