if you are wanting sales then you need to up your game.
I know you have been hit with the critical stick a lot recently, so I am not going to say anything about the game, but the presentation.
And I'm going to do it graphically so you can see what I am on about

OK. first off it would be nice if everything felt like there was some thought and concept. you need to be able to see this without even seeing the game. it gives the feel of the game and the style appears throughout.

Look at the text - compare it to yours. compare it to other similar games. take their lead.
A simple bit of text with a quick filter looks and says: "I'm not really bothered, or could spent the time to come up with a product"
You want people to see the product. everything must look and feel that love, time and effort has been put into it. It it doesn't why should people bother to even continue to look and buy it. You want the first thing that people to see is quality and love

So why did I change the name?
double rr - meh
grum sounds a bit like bum and a game about bums is not what we are after?
grim already sounds interesting and grinthir because it fit nicely with the new graphics element - the shield
So without seeing the game you already have in your mind something with knights, shields, metal and a style.
if Grinthir a place or a person? again this could lead into the back story...
OK, notice there is a very defined graphic element in the shield. is this important? You bet - it's the core graphic we can lift and use for other things to reinforce the game look and style:

So we now have a defined style for the text:
sorta old, with heavy capitals. so this is probably a medieval/fantasy setting - certainly NOT space. unless it was old stye knights in space... You see where this is going

And..
We have the program icon on the left
a timer or direction finder on the right
and we are also using the same logo as a decal for the text
It all says and feels like the same thought and concept.
The game could be a 2d platformer, it could be a full on 3d quake multiplayer, or it could be a rts.