Select the matching Mod-DH variant
The ANSI and ISO row-staggered variants differ on the lower left row, while the ortholinear variant follows aligned columns. Select the matching form before comparing letter positions.
A firmware keymap and an operating-system input arrangement should agree about the characters you intend each position to produce.
Compare against standard Colemak
Highlight changed keys against Colemak, then inspect the lower-row and index-finger positions. Use the same writing sample in the analyzer to see how the changed positions affect its key and finger counts.