Since 2010 we have been using SQL/RS as our main platform to render market research reports. Extracting our reports to pptx has always been succesfull. Last july we moved to a new server and exporting to pptx creates problems. Graphics are set in different places. Headers are not in the right position. Exporting to pdf is without problems.
I have observed the information shared by you and like to share that Aspose.Slides has no dependency upon Office 2013 or jour dll. All it does is to integrate it self with report server. I suggest you to please try using Aspose.Slides for Reporting Services 5.2.2 on your end first. Please verify the report on your new server as well as old server if it is in use using the specified version to see the difference in reports. If there is an issue with using the mentioned API, then please provide the sample report along with data source, RPL export of your report, generated presentation, PDF and tiff export of your report. Please also share the complete SQL server version used on your end as well. I will be able to further observe the issue once the requested information will be shared.