Although you may be aware of these studies, here are a few studies that have employed the French version, many do not assess the psychometric properties directly, but you can extrapolate from them (e.g., what is it correlated with, etc.):
Bernard, J. Y., De Agostini, M., Forhan, A., Alfaiate, T., Bonet, M., Champion, V., ... & EDEN Mother-Child Cohort Study Group. (2013). Breastfeeding duration and cognitive development at 2 and 3 years of age in the EDEN mother–child Cohort. The Journal of pediatrics, 163(1), 36-42.
Bernard, J. (2013). Déterminants nutritionnels précoces du neurodéveloppement des enfants de l'étude EDEN: rôle des acides gras polyinsaturés (Doctoral dissertation, Université Paris Sud-Paris XI).
Halbwachs, M., Muller, J. B., de La Rochebrochard, E., Gascoin, G., Branger, B., Rouger, V., ... & Flamant, C. (2013). Usefulness of parent-completed ASQ for neurodevelopmental screening of preterm children at five years of age. PloS one, 8(8), e71925.
Troude, P., Squires, J., L'Hélias, L. F., Bouyer, J., & de La Rochebrochard, E. (2011). Ages and Stages Questionnaires: feasibility of postal surveys for child follow-up. Early human development, 87(10), 671-676.
You may wish also to contact the company, they frequently have this kind of information:
I am quite impressed to see your interest in attitude towards medication,I am interested in that issue especially medication for clients with psychiatric conditions .I teach Substance Abuse Counselling Course.we may collaborate in future.My hands are full now.
I have come across two in the past ,they are old but you may get ideas from them,here they are:
1.Barbara R. & Margaret W. L (1973), A Scale for the Measurement of Attitudes Toward Drugs,
International Journal of the Addictions, Volume 8, 1973 - Issue 5.