Can you manually create your VPN?
One of the few things I’m very disappointed in KDE is that their implementation of Network Manager is missing a number of features (I’ve found mainly apply to IPv6 and advanced interface options) that are found in the Gnome Desktop and the source codebase. KDE apparently has discussed this since at least late spring last year but still no changes…
I wish I could assist more, but my company uses a PPTP VPN instead. Anyway, I have the same openvpn packages installed (KDE4.6.5), so I think that’s all ok. Now, if I pretend to add an OpenVPN connection, I get presented with the appropriate config screen (as I assume you do too). Without wishing to confuse you, I note there are some bug reports around, which suggest not all .ovpn files are imported properly (due to invalid or unsupported entries perhaps)? For example
for us to examine. (Just post the link to your file here).
Here’s a nice graphical ubuntu openvpn strongvpn tutorial which works for openSUSE too. (I know it is for the Gnome-based NM, but the config steps are the same). Give it a read and see if it helps, or confirms that the problem really is with the .ovpn file
For the moment, I think you could manually configure (as tsu2 already suggested), by opening the client.ovpn file (or whatever its called) with a text editor. Here’s a sample client.ovpn file. You can see it specifies the locations of where to find the ca.crt,client2.crt,client2.key files, and defines the authentication and cipher method etc. So from the info contained, I think you should be able to configure manually simply by reading this text file, then apply using the NM config screen accordingly. If you obtained the .ovpn from a Windows machine, you will need to grab these other client certificate and key files first, then put them in your home directory (or perhaps /etc/openvpn)
Here’s a openVPN guide that may offer the necessary insight on how this all works
Again, if you get stuck, post the contents of the .ovpn file, and I sure that someone will be able to assist further with getting VPN connectivity working tor you.