Measures based on history table

Thanks danextian I see that it is now working for the counts and latest line date. 

I believe there are still a few gaps in this.  Maybe the result I am looking for cannot be acheived?  I still am in need of being able to use my connected date table to select a range of appointment dates, but then I need my disconnected date table to on or before the minimum date selected from my connected date table.  Example is if I am looking at all appointments scheduled for 2/1/23 - 2/8/23, I want to count ALL of the unique appointmentIDs that were NOT cancelled before 2/1/23.  If they were cancelled, I want to see the appointment there still, but I want that count to be 0.

Right now, the disconnected date table is has to be manually adjusted and then also, all of the cancelled and Rescheduled appointments do not show up in the table when I include the 'Count' measure in there.

I am trying to figure out how to tweak this, or if I need to create some sort of relationship between the 2 date tables.

You have been extremely helpful so far and I appreciate you.  If you have any tips on the last little bit that needs to be tweaked I would appreciate it!

Thanks
Ryan