Caster Level for Ghaele character spell-like abilities

[SolitonMan]

I'm running a ghaele character in a campaign using the progression from Savage Species, which the DM has allowed me to tweak to more closely match the final stats in the 3.5 SRD (for example, I get resistance to fire and cold, not acid and cold, and damage reduction is overcome by cold iron and evil). The one area I can't figure out how to adjust is the caster level for the character's spell-like abilities. Savage Species pegs advancement to hit dice, but explicitly says to 12th level. Yet the ghaele only advances to 10 HD through 20 levels of progression. The SRD version of the "full-grown" creature has a CL of 12 for spell-like abilities. How do I account for this, and gain the full CL power I should have for this character?

Thanks in advance for any help/advice.

 

[sukael]

I'd say Caster Level = HD, but with a +1 boost at 7th and 17th ECL.