Hi, Karthik,
you should build your action in a way that you click the dropdown so that it shows the options (you put the wait stage to wait for drop down values to appear) and then you can try to spy the values with one of the modes (as you described may be only UIA would work) if none works you need to send global send keys to the application to get to the right position. The other option could be that you succeed in spying the element as combo box even in UIA and then it is recognized as drop down and will offer you an action like Select Item.
Regards,
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Zdeněk Kabátek
Head of Professional Services
NEOOPS
http://www.neoops.com/Europe/Prague
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