You can’t really tell anything from a few hundred downloads.
You need several months and at least 1000 real and voluntary (not auto) downloads to be able to judge.
Nothing is fast in this business, many players deposit months after they signed up, like Bernie says, because of mailings.
I often send more real downloads than that and see no results from them. It depends also on what exactly I am promoting about the casino and whether the players see it right there when they land.
Using appropriate landing pages can help a whole lot.