To show how the same things apply to the 2-colors game, here are some examples with many of the same misplays featured on earlier pages, but here in the smaller game.
These examples come from two different games.
It immediately creates an I3 and a T4 leak,
and it isn't much of a threat in either direction.
Lacking a good move in the middle, Orange might do well to simply mimic Purple's move, as shown here with this F.
Purple's answer was this W, which is also flawed,
primarly because it creates an L4 leak above it.
Simply rotating the W solves that problem.
As we see, it creates too few corners (at either end) to survive long.
Especially vulnerable is the single live corner at the top left,
which is Orange's 'lead corner': the one at the forefront of the attack.
It is killed by Purple's next move, the Y (below).
A couple of moves later, with Orange having played (incorrectly) on the right, all three of those corners are gone, and Orange will play no more on that side of the board.
Orange avoids those problems by choosing something other than L5.
This F, for example has two additional corners that make
the play for Purple much more difficult and ensure further
Orange plays in this area.
Backing up a move, let's look at that right-side Z5 move.
This Z5 also gives Purple a nice alternate way to get to the bottom
Instead of the Z5, this F poses more of a threat, and instead of that big opening for Purple, there is just a 1-hole.
4 of the 5 squares are 'reserved' already, so having played the Z5 (and suffered the blocks on the left as a result), Orange does better to use 'contested' squares near its own corners instead.
The W also self-blocked its upper right corner.
Skipping ahead a few moves, we see this Orange P at the right.
It has two big problems:
1) It leaves only two live corners above it, and they are close enough to each other to be killed together in one move, such as the Purple N below.
2) It does not pose any kind of threat going down, limiting
Orange's future options in that direction.
Note also that Purple's L4 was a 4-square piece, with the 5-square F (or others) sitting on the shelf.
Purple might choose the N here instead of, say, I4, which would *really* kill the corners, since I4 has a nice place along the bottom, below the Orange Y.
Another choice, among others, would be to play the P from the T5.
Instead of P, this Orange N has more corners at the top which cannot be killed by a single move, enabling Orange to play again above, and the opening downward at least gives Orange a chance to play something later if it so desires.
The I3 or I4 leak at the right is inconsequential,
since Purple already has places for those pieces,
and I5 is already played.