A half-elf summoner isn't getting their Favored Class bonus to an eidolan's evolution bonus. It appears that the bug might be in the ARG. When the ARG is loaded the eidolan doesn't get the bonus but is when that book isn't loaded.
Pathfinder RPG for Players
Advanced Race Guide
a homebrew source for a trait (it can be ignored)
The eidolon should have 9 Evo points:
7 - lvl4 eidolon
1 - extra evolution feat
1 - half-elf FCB (1/4 point) 4 times
When ARG is loaded the eidolon gets only 8 points.
Already fixed for 6.07.05