Hi,
That's
true, it's really
frustrating when you want to do something but you
don't really
know how to
do it .!
Now, the first thing, you're posting in the wrong forum because your forum version is 3.7.2 and this forum deals with version 4.x .!
Anyway, that's a moderator talk and not mine .. I entered your forum and the problem as I can see is just like you explained >> No forum_old.gif and no forum_new.gif !! Other Icons like forum_link works perfectly .!
So what you should in order to make this work is this:
- Just change the icons extension from (png) to (gif)
>> e.g. From (forum_new.png) To (forum_new.gif) ..
- Refresh your forum using (Ctrl+F5) from the keyboard ..
- ENJOY .!
This is what I call the old school way

..
If it didn't work - and I'm pretty sure it'll work - just notify me so that I can give you the clean solution for this ..