Hi Kati_bear,
That was quite a while ago where people had enormous signatures which meant some members, especially those with dial up connections were taking so long to download the signatures that they avoided the forum. When the forum was updated Snuggleham (admin) decided to reallow short signatures only within a certain size bracket for pictures. The limits are 468 x 60 pixels. If you can't make your own then I run a
signature shop where I'll be happy to make you one.