Hi, no you're welcome, I had a very quick look, it works but there are issues visible if you use the debugger primarily the block instance variables are wrong.
First thought is to populate them asap either in a loop on creation or use: System/ on loader layout complete/ for each block/ set OldY to block.Y then do the sums from there......
And a little tip while I'm here.
You know you had to include one instance of the block and text boxes, then immediately destroy the block?
Well you can create a new Layout, call it "Unused" and put anything you want the game to create on it. So long as there is an instance of the object in the game on any Layout used or not, C2 will create the object as expected.
So technically you could throw a block and the text boxes on an "unused" layout and just use a blank layout linked to the correct event sheet to make this "game" as per your CapX.
As your games become more complicated you'll find this saves a lot of clutter around the outside of your layouts, very useful with huds etc too as you can design the hud once then just use an include sheet to get it on any layout.
PS
Back to your CapX.
Your block is 50X50 px 100px centres so there is a void of 50px between each stacked pair.
Try adjusting the point of collision overlap from 100px to 80 or 60 and you'll see the upper block follows the dropping block more fluidly as the dropping block only has to move as few as 10 (instead of 50px) to trigger the secondary drop. Just makes it more visual imo.
Conversely if you increase the overlap to 124 you can reverse the effect and make it more "blocky"