If you click on the symbol in the upper right corner of the screen (the A over A) it will show you your sig in BB code. However, it doesn't seem like yours would be overly long, but to get it to work you can try reducing the amount of BB code till it does, such as size, color, italics etc. I don't know what the size limitations are for this board, but if you want the link, you will have to give up some of those to get it to work.
ok, once I clicked on the A/A, and then turned it off, and changed my font to the smallest possible, I was able to "save" it without the error. Then I just kept increasing the font by one point and saved it each time until I got that error, then I went back one font size smaller, saved it, and just kept it at that - it finally worked!!! Thank you!