There doesn't seem to exist any direct way how .iwa files could be converted to anything else and particular not to PowerPoint Presentations (.ppt) through iwa to ppt conversion. The proper conversion to convert Keynote to PowerPoint can be found under key to ppt conversion.
Typically, .iwa files are found inside compressed documents from iWorks (.pages, .numbers etc.) and these replaced the previously used XMLs that were utilized for the document structure.
If you want to convert your document, you will need to convert it as whole, not just a part from inside the archive.
It may be possible to somehow decode .iwa files (they feature Snappy compression) and rebuild some kind of "old" version of iWorks documents, but that seems like highly unreliably and complicated way to achieve things.
Updated: November 29, 2016
This conversion entry was verified by us and conversion was flagged as wrong or not possible.
Usually this happens when the conversion would try to convert different types of data between each other, such as audio to image, or it is not possible because incompatibility between programs, caused by closed file formats, very limited support etc.
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