HI @kferreiro,
Based on what you described, as I understood it looks like the problem is with the selector of the month dropdown…
Try adding the below selector to yours for the month dropdown and see how it works…
"<webctrl aaname='"+SelectedMonth+"' parentid='searchForm' tag='A' />"
Let me know how it works out for you 
If it works, please mark it as the answer because if anyone else is having the same issue they can navigate directly to the answer…
Thanks
Lahiru