Hi,
I upgraded from 15.2.0 to 15.4.0 but it seems like some of the obfuscation of your Java code is causing issues as it breaks Scala idioms:
package slides contains object and package with same name: ms
one of them needs to be removed from classpath
import com.aspose.slides.FontsLoader
^
I have a similar issue with Cells.
Please advise if this is something you can address.