Thanks for the reply. The instructions are easy enough, I think (painfully easy actually...). When installing a block I unzip the file locally and then (using Filezilla) put the files into a new directory into the blocks subdir. If I read the instructions correctly, installation should take place automatically when you start your Moodle admin.
I run Moodle 1.6.3. The only difference I can think of is that Moodle is run from a subdirectory from my main site address. (As I think (sub)directories and paths are relative anyway, this should not make a difference...) (As my Moodle installation is in use on a daily basis at the Business School where I teach I have postponed upgrading to 1.7 for another couple of weeks.)
I tried installing the learning_resources_block again just now: unzipped locally, put the files including the subdirs into the ../blocks subdir into a subdir called "learning_resources_block". Logged into the site as admin, went to configuration and then to Administration, Blocks. No joy... No messages or anything about something new being installed and the new block does not show up in Admin.
Hope this describes things a little better than in my previous post. Thanks for any help you might be able to offer.
UPDATE: Just now I tried (again) to install the "Dialogue" block. Although previously this did not work, it now works! I saw the installation messages and the block is available. (Just before logging into Moodle as admin I had deleted all the files IE stores locally... Who knows...)