Welcome to the forum, John!!!
In BD1, there are only a few small differences:
-Int1 has the B-fly going in a loop instead of around the border.
-Cave N has 3 F-flies deleted (as Sendy mentioned)
I'm pretty sure that NoOne didn't do a version of BD2.
There's many more differences in BD3 (for level1, at least):
-Cave B: The boulders are arranged differently
-Cave D: Same story here
-Int1: There's no InBox
-Cave K: The amoeba box is twice as large.
-Cave L: 4 boulders above Rockford are removed.
Even more changes in BD4:
(most of these make the caves much easier)
-Cave A: Colors and layout are different
-Cave B: Colors are different and Rockford is moved 2 spaces right.
-Cave C: Titan walls are no longer destructible. One more diamond is needed and the bonus diamond value is 10 less.
-Cave D: The boulder layout is different and there is a box of dirt in the middle of the B-flies. The time and diamond values are modified.
-Cave E: The diamond and bonus diamond values are swapped.
-Cave F: The diamonds required and the bonus diamond values are modified.
-Cave G: A lot of the amoeba is removed as well as two rows of boulders on top. The colors are changed.
-Cave H: The colors are changed.
-Int2: The diamond value is changed from 10 to 90
-Cave I: The colors are different.
-Cave J: The destructible titan walls are replaced with normal walls. More diamonds are added plus some random boulders. The diamond requirement and values are changed. The colors are different.
-Cave K: The amoeba box is reduced and the diamond values are altered. The colors are changed.
-Cave L: The diamond values are altered and the amoeba box is different. The colors are changed.
-Int3: One Rockford is removed and one color is changed.
-Cave M: There are random boulders added.
-Cave O: The block of F-flies is altered, some diamonds above are removed, and there is an escape passage added on the right. Diamond requirement is changed.
-Cave P: A nicely designed cave was replaced with an unbelievably easy one that's totally different.
-Int4: A rockford is removed, and there are a bunch of boulders added above the amoeba zone. The bonus diamond value is changed.
(no changes in Int1 and Cave N)
There are too many changes to mention in BD5-11

.
Boulders are round.
Fireflies are square.
I need to find
a'way out of here.