I've never had any problem with my signature appearing - it is necessary to select the option Attach my signature by default: in Control panel->Board preferences->Edit posting defaults.
Now I've just tried pasting into my avatar the URL for e-mails et c. - without the [img]&[/img] delimiters - and hey presto! - my mugshot is there!
If this were my topic, I would edit it to say "Solved!"
BTW, what does "making it sticky" in the topic title mean?
[Edit: Now my avatar shows the mugshot retrospectively - which makes reading earlier posts puzzling for newcomers viewing the topic. I've noticed before that when I change my signature, the change applies to all previous posts, so that if they refer to my setup, it is not correctly represented as it was at the time of the post].
Yours hopefully -
Using a PC with 2GB RAM, 3 hdds and a 1.7 GHz Celeron cpu.