You don’t need to use “Indicate on screen” from the activity, just copy the selector string from UiExplorer and paste it on the selector of the activity.
Did you try running the sample I attached? Did it work?
About your question, as far as I know, there’s no direct way to have two textboxes in a single dialog. For some workarounds and discussion about this, visit Create multiple field input dialog - #13 by zeeshan
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