The font issue seems to be related to the fact that the 현대하모니 L font is not available in the browser, so it needs to be loaded explicitly in order to be used. The same appearance would be observed if you place this HTML on a simple page:
<pstyle="font-family: 현대하모니 L;">
범례
</p>
Regarding the Complex file, there seems to be an issue with the image inside it probably due to the fact that the image is with .emf extension. If the inserted image is a .png, the issue is not observed.
Apart from the images issue, some named ranges are not imported properly due to invalid characters for the names of some ranges. You can test that by removing the image from the file and try loading it again. Here are a few of them:
We encountered 82 errors while reading this file. Please be aware that some formulas might be missing, or contain invalid results.
Context
Error message
reading user-defined name: _?
Can't handle character with code: 63 (input: _?)
reading user-defined name: _?____?
Can't handle character with code: 63 (input: _?____?)
reading user-defined name: ____?____?
Can't handle character with code: 63 (input: ____?____?)
reading user-defined name: __KDX3
External reference not supported (input: [0]!__KDX3)
The Name Manager of Excel is also showing the names with underscores and question marks as in the attached picture.