Update to 9.5, Plugin Problem

Friends,

I just updated RDi from 9.1 to 9.5. (Yeah, I know I should've done that months ago, but, better late than never, right?)

Once I had it installed, I went into RDi and it popped up a window that said something about updating (or was it reinstalling?) my plugins. I was in a hurry at that time, and didn't pay enough attention, I just hit the cancel button so I could get into LPEX and do my editing.

Now that I have some time, I'm wondering how I can get back to that window? I can't find the option anywhere.

Since my plugins are gone, I thought maybe I should just reinstall them by hand. I needed the iSphere plugin, so I downloaded it and attempted to install it -- but now I get an error trying to install it. So I think the whole plugin is stuck waiting for me to go back to that window? Or maybe it's screwed up in my installation somehow?

Here's the error I get trying to install (running RDi as administrator):

Problem Occurred
'Installing Software' has encountered a problem.
An error occurred during the org.eclipse.equinox.internal.p2.engine.phases.CheckTrust phase.

If I click "Details >>" it gives this:

An error occurred during the org.eclipse.equinox.internal.p2.engine.phases.CheckTrust phase.
session context was:(profile=IBM Software Delivery Platform com.ibm.sdp.eclipse.ide, phase=org.eclipse.equinox.internal.p2.engine.phases.CheckTrust, operand=, action=).
Error reading signed content.
error in opening zip file

Thanks in advance for any help you can provide!

-SK