I have the following problem:
Often I copy text from a scientific publication into a text window of PowerPoint. By doing so the carriage returns from the publication is also copied. That means, if I copy 10 lines in the publication I get 10 lines in the PowerPoint text window. I don't like that. I would rather like to have the text in one line.

I envision the following approach to solve this problem:
After pasting the text from the publication into the text window I would like to run a macro which removes the carriage returns in the active text window.

Work outline
1. write the macro that removes the carriage returns
2. Add a button to the PowerPoint menu bar that executes the macro
3. save macro as add-in and activate add-in in PowerPoint

For points 1 and 2 in the work outline above I need help. If somebody could get me started with the macro that would be great. I have Excel VBA but no PowerPoint VBA experience. In regards to the button , I have done that before in Excel. I am trying to adapt this method to PowerPoint. After having had a quick look I figured that adapting the method will not be straight forward. Hints would be appreciated.