Hello Claudine,
Yes it was a bit easier to commit a transform back in AR3!
But as the Transform Tool has been given more things it can do it now needs a Panel of it’s own.
However the following three actions can all be performed on a Stencil without needing to use the Transform Tool in both AR3 and AR6.
But note, in AR3 the modifier key for 2 and 3 are the other way around!

1: To move a stencil around the canvas Right Click and drag.
2: To Scale a stencil up/down hold down cmd key (or ctrl for Windows users I think) and the cursor turns into a Magnifying Glass icon. Now drag left or right on the stencil.
3: To Rotate a Stencil, hold down the Option key (Alt on Windows) and the cursor turns into a rotate arrow icon. Again dragging left or right will rotate the stencil.

To commit transformations on a Stencil when using the Transform Tool you can do one of 3 things;
1: Hit the Return key.
2: Click on the Tick box in the Transform Panel.
3: Click anywhere outside of the Transform Box. However in AR6 when doing this you will still need to hit Return or Escape or the Tick Box to finally get rid of the Transform Panel. This may be a bug in AR6?

For Layers in AR3 you could click anywhere outside the Transform Box to commit the action but this dose not work in AR6. This too might be a bug?
So currently in AR6 you have to hit Enter or click on the Tick Box in the Transform Panel.