Hi tgc. Thank you for your fast response.
First - The VLC 32-bit solution on Windows you mentioned is well understood, but I don't plan to uninstall the 64-bit I already have; however I'd like to ask a question: Will VLC 32-bit portable work if I install it on a local disk while I have the 64-bit version also installed on a different disk (http://portableapps.com/apps/music_video/vlc_portabl)? OpenLP doesn't seem to allow the selection of a directory to assign a player executable, which is a shame.
Second - As to the LibreOffice issue: I refer only to an Impress presentation. When I have a presentation live (on a 1-screen setup) I have to use the arrows keys on the keyboard to change slides. Using the mouse to accomplish that doesn't seem to work or I am missing something.
Third - With regards to the mouse having more power on a live presentation: I don't see slide-controller on screen when an Impress presentation goes live, or, again, I may be missing something.
Will you please help?