You can simply print any PowerPoint slideshow (.pps, .ppsm, .ppsx) or presentation (.ppt, .pptm, .pptx) to a PDF file using virtual printer via the Print... function in several presentation software programs, or with the PowerPoint itself. MS Office installs PDF driver by default, so easy enough.
Convert Microsoft PowerPoint macro-enabled Open XML complete slide show to Adobe Portable document format.
We have found one software suitable in our database for this conversion.
Articles and other information relating to ppsm into pdf conversion:
How to print anything to PDF using virtual PDF printer - Create PDF documents from any Windows application that is capable to print using PDFCreator
Microsoft Windows software - convert ppsm to pdf on Windows
A presentation program from the Microsoft Office suite
Convert from ppsm file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.