Counting to 26 from Kb1-12 instead of from Kb1-11 seems unavoidable:
 
24 24
Ka4-15 Kb1-10 Kb1-11 Kb1-12 *Kb2-15
1 26 1 26
'summer'

Rei at Kb1-11 cannot be counted if we wish to have an equal number of glyphs at left and at right in 'summer'. The pattern is that Rei glyphs do count when we sum up to 150 or 168 but not when we sum up to 20 or 26:

Ka2-1--Ka2-9 9 84 168
Ka2-10 (Rei) 1 75 150
Ka2-11--Ka3-14 26
Ka3-15 (Rei) 1
Ka3-16--Ka4-14 'spring' 20
Ka4-15--Kb1-10 'summer' 26
Kb1-11 (Rei) 1
Kb1-12--*Kb2-15 26 75 84
*Kb1-16--*Kb5-11 49
*Kb5-12--*Kb5-20 9

The structure shown in the table probably is, however, just a small part of the overall layout. For example: 168 + 24 (the number of glyphs in the first line Ka1) = 192 = 8 * 24, hardly a random number.