Is the mate supposed to be forced?
My engine prefers 1. ... Rxe4 (Western algebraic notation; I suppose it's R5+1 in traditional notation) and then it doesn't find a mate (but it gives a large advantage to White/Red). If I enter 1. ... Exg6 (E5+7) it finds the mate immediately.
How did Red ( to move ) achieve checkmate from this position ? ( A game from China on June 8, 2016 )
If you have problems with the notations, consult :
www.xqinenglish.com
Highlight the following space for solution:
1. R3+2 E5+7 2. H2+4 K5=6 3. C7=4 R5=6 4. H4+2