Work hours do not interfer with resource planning.
Work hours are only taken into account for :
- convertion from hours to days (and must be fixed for all resources)
- calculation of indicators in worked hours (and must be fixed for all projects)

For exemple I've in my team some people who works 5 days/week and 7 hours/day
but I've other people who works 4 days/week and 8.75 hours/day

I can't manage this (or I don't find how...)

No,
This case cannot be managed with ProjeQtOr. 🙁

And I don't know any Project Management Tool that can do it. :ohmy:

Yes, "Open Workbench" can do this
In fact, like Projeqtor, you can create calendar, but you can, in each calendar, chose numbers of working hours

But how does it manage conversion from hours to days for all resources ?
When you display work for all project in days, how is done conversion from hours to days for all resources ?

I guess there is, like in MS-Project, some global definition of convertion.

So hours on resource calendar will only define working period.

You can get the same changing the capacity of the resource.
For instance, define work period of 8 hours a day.
Resource working 7 hours a day have capacity of 0,75.
Resource working 9 hours a day have capacity of 1,25, and a specific calendar with only 4 working days per week.

" When you display work for all project in days, how is done conversion from hours to days for all resources ?"

"For instance, define work period of 8 hours a day.
Resource working 7 hours a day have capacity of 0,75.
Resource working 9 hours a day have capacity of 1,25, and a specific calendar with only 4 working days per week. "

==> it makes same thing than you propose to me
I've 1.25 days / day 🙂

thanks for your help, your solution works perfectly !