Crashing imply an error screen, with some numbers on screen to help developers understand what happened and fix it.
In your case, I think it doesn't "crash", it returns to/reloads the system menu.
when it's doing that, it means the loader couldn't find the game.
so, many possible reasons :
- verify the path to the game, the folder name, the file name. (/wbfs/Game Title here [TitleID6 here]/TitleID6.wbfs)
- verify the game's files (.wbfs) are not write protected
- verify they are good (use wii backup manager > option > sha1)
- in the loader, verify you are not using an individual setting for these games with an IOS slot different than the global option.
- maybe other possibilities, I'm not thinking about them right now.