problems with opening slidesows I have made in powerpoint
Your description of the problem is confusing. You say “use powerpoint to open” and “made in powerpoint”. Which is it? (If it is both then it has nothing to do with LibreOffice.) Please Edit your original question to give us more specific information.
Sorry about the poor punctuation. I made the slideshow in libre office and tried to open it in power point.
OK, had you saved the document in LibreOffice’s native Presentation format (.odp) or had you exported it as a PowerPoint file (.ppt)?
I ask because, when working with a LibreOffice document, it is generally recommended to always save it in the LO native format (.odt, .ods, .odp), and to only/always export it to use with other software (expecting formats like .doc, .xls, .ppt). Using PowerPoint to open a .odp file might explain the unintended changes that you found.