Simply require support of standard file formats.
ppsx should look and work the same in Microsoft Office as it does in Impress, if it doesn't it is probably the fault of Microsoft, the programs are saving files with a slightly modified format - remember standards may be published binaries are not or a feature in the Powerpoint file format hasn't been implemented yet in Impress. Being standard and published it should be added by the programmers at OpenOffice.
Do you get it? Create in Power Point test in Impress. Create in Impress test in Power Point.
If you are a company I own stock in you better be working on saving money. If you have a person that can't do it with Impress maybe you should be retiring the old fellow or gal and hiring someone that is more flexible/capable/younger.
If you are a Government agency it is obvious that incompatibility is a part of the Microsoft offering. My advice - require standard and open file formats. 100% of your users should be able to open it now and probably 100 years from now. If you go with proprietary and slyly changing formats you will find that many of your users cannot use your service or open your files.
For example: in the United States I suspect that Obama could publish an executive order directing the executive branch of the Government to use standard open file formats and that would be it.......
Biting the hand that feeds IT
