The original points \( K(-3, 4), L(-3, 5), M(1, 5), N(1, 4) \) are dilated by a factor of \( 0.25 \). The dilated coordinates are calculated as follows:
\[
K' = (-3 \times 0.25, 4 \times 0.25) = (-0.75, 1), \quad L' = (-3 \times 0.25, 5 \times 0.25) = (-0.75, 1.25)
\]
\[
M' = (1 \times 0.25, 5 \times 0.25) = (0.25, 1.25), \quad N' = (1 \times 0.25, 4 \times 0.25) = (0.25, 1)
\]
Thus, the dilated points are:
\[
K'(-0.75, 1), \quad L'(-0.75, 1.25), \quad M'(0.25, 1.25), \quad N'(0.25, 1)
\]
The dilated points are then rotated \( 90^\circ \) counterclockwise about the origin using the rotation matrix:
\[
\begin{pmatrix} 0 & -1 \\ 1 & 0 \end{pmatrix}
\]
The rotated coordinates are:
\[
K'' = (1, 0.75), \quad L'' = (1.25, 0.75), \quad M'' = (1.25, -0.25), \quad N'' = (1, -0.25)
\]
Next, the rotated points are reflected across the \( y \)-axis. The reflected coordinates are:
\[
K''' = (-1, 0.75), \quad L''' = (-1.25, 0.75), \quad M''' = (-1.25, -0.25), \quad N''' = (-1, -0.25)
\]
Finally, the reflected points are translated \( 3 \) units to the right and \( 7 \) units down. The translated coordinates are:
\[
K'''' = (-1 + 3, 0.75 - 7) = (2, -6.25), \quad L'''' = (-1.25 + 3, 0.75 - 7) = (1.75, -6.25)
\]
\[
M'''' = (-1.25 + 3, -0.25 - 7) = (1.75, -7.25), \quad N'''' = (-1 + 3, -0.25 - 7) = (2, -7.25)
\]
The final transformed coordinates are:
\[
K''''(2, -6.25), \quad L''''(1.75, -6.25), \quad M''''(1.75, -7.25), \quad N''''(2, -7.25)
\]
Thus, the final answer is:
\[
\boxed{K''''(2, -6.25), L''''(1.75, -6.25), M''''(1.75, -7.25), N''''(2, -7.25)}
\]