Is there any update on the hypothesis on primary emotions corresponding on "love"?
This hypothesis relies on a number of ideas that are difficult to defend in light of the past decade of emotion research.

Most notably, there is almost no evidence of modular "emotion systems" in the brain that coordinate some sort of stereotyped emotional response (1 2 3 4).  

Moreover, rigidity in responding is often related to reduced evolutionary fitness.  High fitness species have behavioral and genetic flexibility (see the evo-bio literature on degeneracy and variability).

Moreover, there's strong evidence that the brain is predictive, not reactive (for a starting point on this idea, see 5), which rejects the traditional stimulus-response paradigm (e.g., "triggering" a circuit).

The theory also relies on an outdated understanding of neurotransmitter functions (e.g., 6 7).

Overall, this theory needs to be heavily revised in order to account for contemporary findings.