When the attached file is output by aspose, the text is no longer editable (it appears like an image instead of text). This appears to be caused by multi-column text fields.
I have worked with the presentation file shared by you and have been able to observe that the Autoshape containing the text is converted to image in saved presentation. An issue with ID SLIDESNET-36632 has been created in our issue tracking system to further investigate and resolve the issue. This thread has been linked with the issue so that you may be automatically notified once the issue will be resolved.
We are sorry for your inconvenience,
The issues you have found earlier (filed as SLIDESNET-36632) have been fixed in this update.