Hi SAT,
I have observed the requirements shared by you and like to share that when the used fonts inside your presentation are missing in your operating system, Aspose.Slides use Arial as default rendering font. You need to install the fonts on your end in your desired machine to get the correct rendering. If you don’t ought to install the fonts in your target machine, you can copy those fonts in your target machine and load them externally using Aspose.Slides without even installing them. The following sample code will help you in this regard.
String FontDir=“c:\FontPath\”;
FontsLoader.LoadExternalFonts(new String[] { FontDir });
Please share, if I may help you further in this regard.
Many Thanks,