Converting producer files back to PowerPoint

Hiya,

I made some very complex and time consuming PowerPoint files which I
converted into Producer files and then posted online. However, I then lost
the disk with the original presentations on them.

I was able to retrieve the Producer files, but need, if there is, a way of
"deconstructing" the producer files back into Powerpoint presentations.

Someone suggested asking on this forum, so here I am.

Any ideas?

Thanks