I like to share the announcement of the release of Aspose.Slides for SharePoint 1.4.0. In this release, we have added support for combining multiple presentations into one single output presentation. Now, you can merge PPT and PPTX presentations together and export them to PPTX.
To view a complete list of fixes and to download Aspose.Slides for SharePoint 1.4.0, please visit the download section.