** Shares of LNG producer NextDecade NEXT.O fall 6.3% to $7.18 after Morgan Stanley cuts rating to "Equal-weight" from "Overweight"

** MS also cut its PT to $10 from $15

** Brokerage says NEXT's recent final investment decision on Train 4 of its Rio Grande LNG project in Texas brought clarity on costs and timeline, but updated financial outlook disappointed

** Says NEXT now expects about $1 billion in annual cash flow from five trains, at the low end of its earlier $0.9 billion to $1.3 billion range for the full 5-train project

** High financing costs are also weighing on the outlook, MSadds

** For Trains 4 and 5, NEXT implied sales and purchase agreement rates are $2.54 per mmbtu, lower than MS's prior forecast of $2.63

** Including session's move, stock down about 7% YTD

(Reporting by Dharna Bafna)

((dharna.bafna@thomsonreuters.com))