It is not possible to enter the date directly in the RxDBGrid if the date field is empty. There must first be a date so that you can enter a date with the keyboard. I have rewritten the procedure TRxDBGridDateEditor.EditChange in rxdbrid.pas (from line 2704) so that the date can also be entered directly on the keyboard.
The limitation of the year "if not ((iye> 1899) and (iye <2200)) then b: = false;" can be omitted or transferred to properties.
I have not yet checked whether the procedure may need to be adapted to other system settings. It could then be that a different pattern is used instead of "dd.mm.yyyy" However, this can easily be adjusted.
I have attached a new File which takes into account the system settings for ShortDate Format.:"TRxDBGridDateEditorEditChangeSystemDate.txt" .
Since I have not found any contact details for the developer / translator, I post the procedure here. It may be helpful for some.