Ok, it seems to work.
You will use the official B4XDialog (it is part of the Xui Views library) and its ShowTemplate method but, as you can see in the project I attach, you will add and use this class, lmB4XDateTemplate, add and use also the layout file DateTemplate2.
I repeat that the purpose is to be able to highlight N days of the month (and, at your choice, make only them clickable or all days).
You can choose whether to highlight the days with circles or rectangles.
Obviously, it is not necessary to "associate" a DB to the dialog-template, you will pass a list of numbers, the days of the displayed month to highlight (see how in the project).
Yet I believe that this is precisely the case in which the class is most useful, with a DB table. In the attached project, the example is really minimal: some (few) days are "associated" with a record of a table, which contains only a date and a note. By clicking on a highlighted day, the relative note will be taken from the DB and displayed in a MsgboxAsync.
Since this is just a demonstration of the use of this class, I have not added code for editing, deleting and creating a note.
I do not have Apple HW, so not even B4i and I could not create the layout for this platform, but for you it will be a breeze, you just need to open one of the other two IDEs, the layout, copy the views and paste them into the B4i Designer.
Finally, do not forget to offer me a coffee

, otherwise how could I stay awake at this hour (about 3:37 AM)?
[Erel, if you want to use this class and the ayout instead of your originals, not only can you do it but I would be very happy (and it would be very convenient).
Note that for the month and year selection I used two B4XPlusMinus, eliminating the 6 views that served this purpose].