Cannot activate or use plugin after updates

I am running nextgen and nextgen-plus on the site lizrideal.com, and recently updated both plugins to the latest versions. However, I found that the site broke after this update, so I deleted both plugins and uploaded them fresh via FTP.
I can activate them, although the process is extremely slow, but then cannot use them at all (for example clicking on Gallery settings eventually results in a timeout error).
Most of the site content is nextgen galleries so I really need to find a solution to this.. Any suggestions as to why this would be happening?
(I have already tried de-activating all the other plugins in case of conflict but this doesn’t help)

The page I need help with: [log in to see the link]