"ERROR Install Package Not Available"

Hi there, I am trying to install plugins from the WPMU Dev tab but get the error “ERROR Install Package Not Available”. In fact, I cannot even post a support ticket from there as the page hangs. If I upload the regular way (i.e. download the plugin, then upload in wordpress plugins) I can do it. I did notice, however, that there are several issues with some of your plugins I tried to install, but with wait to resolve this issue before I post as they might be related.