The RSS feed is private by default. You install a client (like Sharp Reader under Windows). It stays in the icon tray and periodically checks for new ELOG entries. If there is one, it pops up a window similar to your email client. You click on it, and it shows all entries like this:

 All you have to do is to enter the URL of the ELOG logook. Just add "elog.rdf" to the URL of the logbook as you would access it from your browser.

Here is the pop-up I got from writing just this entry:

Thumbnail display in "full view" is implemented already. Let's take this entry: I insert a picture and scale it down via the "smaller" button:

Now if you display this forum in full view, the image is still shown as a thumbnail, which you are able to click in order to get the full resolution display. I don't know what is different in your case, maybe you are using an oder version of ELOG?

Attributes = ..., Flag, ...
Options Flag = Yes{0}, No{1}

{0} ...

{1} ...

Please read the FAQ

You can do this by defining groups. For this forum I did

Group Demo = Linux Demo, Database
Group Discussion = Forum, Config Examples, Contributions, Vulnerabilities

where each name on the right side of the equal sign is an individual logbook.

I found a way to get this to work.  Define a "Messages" logbook for the messages to be broadcast.  None of the user installations need access to it. Use "Execute new = " to execute a script calling the elog command line client passing the message on to each target logbook.  Example:

--- elogd.cfg snippet begin ---

[Messages]

...

Execute new = mass_post.sh $text &

--- elogd.cfg snippet end ---

--- mass_post.sh begin ---

#!/bin/sh

elog -a Sender="System Administrator" -l "Logbook 1" $@

elog -a Sender="System Administrator" -l "Logbook 2" $@

elog -a Sender="System Administrator" -l "Logbook 3" $@

--- mass_post.sh end ---

The $@ expands to all the command line arguments, so the $text field, with all its spaces, gets passed correctly.  Sorry I showed you the example in bash/linux rather than in Windows, but I don't know Windows real well - you're better off translating into it yourself than my untested attempts.  The one thing I can tell you is that the "Execute new" command must include the "background fork".  In Linux this is provided by the & at the end of the line. In windows you'll need to use

Execute new = start "dummy" /min mass_post.bat

to background the process.  This is ESSENTIAL.  Without backgrounding the batch file, the elogd server will go into an infinite loop.  The parent process will wait for the child process to exit before continuing.  elogd is single-threaded, so the child process cannot start until the parent process has completed its current task (which is waiting for the child process to exit). 

You may need to tweak the above a little if you want to pass variable attributes to the script instead of defining them all in the script itself.

I tried to reproduce your problem, but it worked fine for me. I used in elog.cfg:

[demo]
Attributes = Icon, Author, Type, Last Edit, Subject
IOptions Icon = icon1.gif, icon2.gif, icon3.gif, icon4.gif, icon5.gif, icon6.gif, icon7.gif, icon8.gif, icon12.gif, icon13.gif, icon14.gif
Quick filter = Icon

Then I entered two entries with different icons, and I selected the quick filter. It correctly showed me the entry with the icon I selected: