Siege Tower Glitch... Any advice?

[bugrat]

In my most recent campaign as Hayasdan, when I do battles involving siege towers, I get this really annoying glitch every so often where the soldiers get stuck before entering the tower, and just kind of jiggle around down at the bottom of the tower for the entire battle. Sometimes this happens to my own units, and sometimes the AI's. This picture shows what I'm talking about:

http://www.imagedump.com/index.cgi?pick=get&tp=534906

This doesn't happen 100% of the time, but in the battle that the screenshot is from it happened in 2 out of 3 of Pontos' siege towers. The only way for me to finish the battle is to move my troops out of the gates and attack the tower from behind. This takes just a massive amount of time, and sometimes the siege tower randomly starts working again and the enemy troops will walk up and capture my gates while my troops are trying to get up behind them! So frustrating ha ha...

Now what I'm wondering is if anyone else ever experiences this glitch? If so, I'm looking for a workaround.. Alternatively, are there any cheats that I can use to get around this? Is there any way to instant kill a unit when it's stuck? Also, if I'm surely going to win, is there any way to quit out of a battle and have it count as a win (Like "auto_win defender" while a battle is in progress)

Any help would be greatly appreciated..