Here's a script that shows the note text from the currently selected row in Marked (version 1). I made it use the standard version of the application, but it should probably work with Professional as well. I have it set up as a toggle button on my toolbar as shown here. If Marked is open, clicking the button causes it to quit. Otherwise it pops up and floats with the text of the notes for the selected row.
if application "Marked" is not running then tell application "OmniOutliner" set xNote to note of selected row of front document as text end tell do shell script "echo " & quoted form of xNote & "> /Users/YourUsername/some_file.txt" do shell script "open -a \"Marked.app\" $HOME/some_file.txt" tell application "Marked" --This part keeps Marked on top activate tell application "System Events" key down command key down shift key down "F" delay 0.5 key up command key up shift key up "F" end tell end tell else tell application "Marked" quit end tell end if