Hi Philippe,
Greetings from Syncfusion. We were able to reproduce the issue “Small level ranges not showing properly in numerical axis” and we have created a new support incident to have further follow-ups regarding this. We will assist you through incident under your Direct Trac account.
Our Direct Trac support system can be accessed from the following link:
http://www.syncfusion.com/Account/Logon?ReturnUrl=%2fsupport%2fdirecttrac
Regards,
Michael