[Stage] Custom stage invisible wall?

[Divisor]

Check the stage data, you should see something like this:

Code:

<stage> id: 50  #Survival Stage
        <phase> bound: 1500  # phase 0   bandit
                music: bgm\stage4.wma
                id: 122  x: 100  #milk  ratio: 1
                id: 30 hp: 50  times: 1
                id: 30 hp: 50  times: 1  ratio: 0.7
                id: 30 hp: 50  times: 1  ratio: 0.3
        <phase_end>

For your problem, you need to look at "bound:" nex to the "<phase>" tag.
As Someone Else said, you need to decrease this "bound:" so it becomes smaller than the width of your background and thus actually reachable.