regards to "inline images..."
can you add an ALT-tag for [att achthumb=#]-tag
or can you not only insert the [att achthumb=#]-tag
but [att achthumb=#] Thumpnail preview, click on picture for full size ?
i.e. not only the tag itself but an text also.
If users don't want this text they can delete them.
But other users see that this pic is an thumpnail only by this text.