Horizontal lines when using Lighting Effects in Photoshop CS2

[NeoDaitou]

I'm new here, so I'm not sure if this is in the right forum or not, but hopefully if it isn't it can be moved (or at least someone can tell me so I can repost it in the correct forum).

I've been trying to follow Ascension's Atlas tutorial and I got to the part where I need to use the lighting effects on the mountain layer. Unfortunately, when I follow the steps, I seem to have horizontal lines that are affecting the rendering (see the attached picture). I've tried adjusting each of the settings of the Lighting Effects dialog box, but nothing seems to be causing the issue. I can get rid of the lines with the healing brush, but that is incredibly time-consuming and not a perfect solution for the issue. I'm using Photoshop CS2 if that helps anyone figure out why this error keeps happening. I also tried this on a new image filled with nothing but a simple grey background and I got the same effect, so I don't think it's an issue specific to my file.

I would appreciate any help I can get as this is effectively stopping me from continuing and I'm trying to work on a map for an upcoming campaign.

Thanks in advance,

~NeoDaitou~

[Trok]

I'm having the same problem