In this particular version of libreoffice KDE, the zoom slider is missing.
Really only Presentation? Ever confirmed?
Not reproducible in 3.5.1 on Fedora 64 bit, KDE 4.6.5
This's fixed with 350m1(Build:102) (probably by mistake).
<https://bugs.freedesktop.org/page.cgi?id=fields.html#status> we should used FIXED only if a known fix has solved the problem; if the problem only disappeared without known reason, please use WORKSFORME.