Font rendering issue with aspose plugin dll

Hi,
I use Aspose.Slide.dll which enables to parse and render powerpoint shapes and slides into unity textures. Everything works well inside the editor but when running in a standalone, it looks like the plugin cannot acces to the system fonts and so use a default arial font.

I've been digging on the web a lot and i didn't find any usefull help. Is this a security issue? Does anyone know how could it be?