We were able to employ XSL Transform technique to very effeciently generate a part (sheet.xml) of Open XML workbook. I have talked about this whole scenario at the following post:

How to efficiently generate OpenXML Workbook from Excel files containing very large amount of data – Visual Studio Office Development (VSOD) Support Team – Site Home – MSDN Blogs

This method is quite fast as well as extensible. During my testing, the generation of an Open XML workbook from a data XML containing around 1150 rows with 30+ columns each, took even less than a second to generate. Also, this technique can be extended to pull in data from a back-end database as XML and generate Open XML workbooks on the fly.

Have a look into this article and feel free to drop you comments/queries here or on the above post, I will surely try to answer them.

If you have a Chart in an Excel workbook, and you want to insert this chart as link in a PowerPoint Slide by using Paste Special, it may fail to paste anything in the slide if the current view is Outline View.

Also, even if the current active tab on the Normal View of a PowerPoint presentation is Outline View and it has the input focus, PowerPoint will fail to paste anything. And, the stranger part is that you will not get any message box informing so!? (…not surprised!)

How to avoid this:

You can paste the chart by following any of the following ways:

1. Close Pane 1 of Normal View.
2. Activate the Slides tab in Pane 1 (see screenshot below).
3. While keeping the Outline tab as selected tab in Pane 1, Activate Pane 2 (Slide pane) by clicking in it, before you select Paste Special.

Please note that you may encounter the issue even if the Outline tab in Pane 1 is activated and it has input focus.