That makes sense. The text is configured to use system fonts, but those fonts aren't present on the non-Korean machines. As a fallback, we try to find the next closest font available on the system, which is totally wrong. The nice thing about system fonts is that you don't need to include any font data in the Flash movie (SWF) which reduces download size, but if the fonts you need aren't present on the system, then you get our best guess. If you have no fonts on your system that can display Korean, that's not going to work well.
Alternatively, when you're authoring the Flash content, you can choose to embed the font into the SWF such that it gets displayed correctly. This increases the size of the SWF by the size of the font(s) used, but you're guaranteed to get consistent rendering across devices regardless of the fonts available on the user's system. Alternatively, if it's just an Intranet site, your IT department could ensure that the correct fonts get installed onto the non-Korean systems across your enterprise.
