Well also with some installers the control ID give is not the right one...see this a lot with TEdit2 controls and the like.
Also some times controls need focus before using any of the edit field commands...reguardless if its ControlSetText, ControlSend, or Send
So my prefs are:
1st ControlSetText (fastest)
2nd ControlSend (better window control)
3rd Send (f*** it)

So if you have a control that giving you grief try the following first..if changing controller ids doesn't work first.
ControlFocus ( $title , "" , control_id )
ControlSetText ( $title , "" , control_id , "string" )
If that fails try ControlSend in much the same manner...really do try to avoid sending blind Send commands.
My thoughts tho