[otrs] Installing additional opm packages.

I have been trying to install additional packages with the opm extensions using package manager but each time click on the install button,I get an error.I do not have direct internet access and the only way that I have attempted to download these packages was to right click and select to save this target.Any ideas. Can't get file from http://otrs.org/repository.xml: 500 Can't connect to otrs.org:80 (connect: timeout)