Hello again,
I updated Telerik with the last version available and it is better but I still have the same problem in some cases.
When I enter the number 0.00000001, it is correct (see first image 001.png).
But, just after encoding the value, if I re-enter inside the console (with a click of the mouse for example) then the value is transformed into 1e-07 (see second image 002.png).
And it is, unfortunately, the 1e-07 that is always sent to my .net controller method.
Thank you.