Thanks for inquiring Aspose.Slides.
I have tried to observe the requirements shared by you. I like to share the Aspose.Slides (for PPT) and Aspose.Slides.Pptx (for PPTX) are two separate namespaces dealing with two different formats of presentations. What I have observe from your requirement is that your need to add or access particular row or columns inside PPT table.
Actually, the eventual purpose of working with table is to access some particular cell inside table and play with its values. In case of PPTX table, we have collection of rows or columns associated with table and you can access the cells either by traversing through columns or rows. So, its a two step approach for accessing the cells in case of PPTX. Similarly, you can add or delete the rows or columns inside existing tables as well.
Now, in case of PPT table there is no collection of rows or columns exposed for access. But a direct method to get the particular cell by providing its row and column index is available. PPT tables allows you to add new rows or columns as well. In short, it has all the capability of PPTX tables but has missing collection of rows or columns as in case of PPTX. But it does give access to particular cell by providing row and column index. I don’t feel its an issue. Can you please share the requirements that you are trying and not getting them done through PPT tables.
Secondly, we are also working over the unification of Aspose.Slides API for both PPT and PPTX. The new API is expected to be released during Q2 of 2013. Once the new API will be released there will be same access methods for dealing with PPT and PPTX presentations.
Please share, if I may help you further in this regard.