Simple CSS question (I think)

[shadow5561]

I just started brawl hacking and I decided to start with small things. So I downloaded ASF1nk's Dark Flaming Blue CSS (Normal). I decided to start with switching CSS icons just to start. I get Brawl Box and open ASK1nk's CSS then go into MiscData[70] then I do a simple swap of Mario's icon with the magical replace button. I pop in my SD card try to go to training mode then BAM my wii froze. What did I do wrong? And will other problems happen if I try to switch out anything else from the CSS?

[SmashHackers]

The problem probably isn't from switching that one icon. Did you change anything else?

[shadow5561]

The problem probably isn't from switching that one icon. Did you change anything else?

Not at all. I then redownloaded just to make sure I didn't and went back in with brawl box and only changed one icon again. Try to load it agin and it still doesn't work.