Forum:Stuck on a plot mission - Can this stuck addons?

Hello everyone! I'm new here, but I've been playing Borderlands for a while on my Xbox 360.

When I started playing Borderlands, first as a Hunter, I got up to about 26 level, having "Get Off My Lawn!" as the plot mission.

Well, I went online once again, only to find myself stuck in the mission "Keep Your Insides Inside" where you have to buy a shield. Note: this was playtrough 1.

I tried to turn in the mission once I bought the shield, but obviously couldn't because Zed had already left Fyrestone. I read some forum pages about the problem and discover joining an online match with a person completing that mission the only chance to get moving again. The only matches I found with this plot mission were just other guys stuck in the same mission.

I couldn't continue the plot, and playing like that seemed pointless, so I started a new playtrough as a Soldier. I haven't dared to go online with the Soldier, because of the virus-like spreading mission glitch, and I've soloed my way trough both playtroughs and I've purchased the Zombie Island and the Secret Armory add-ons.

What I want to ask is more specifically this: Will there be any chance to get stuck in that or other alternate missions (I've heard there are more of them than this one) once you've beaten both playtroughs, if yes, will it stuck the add-on storylines as well?

I would've tested the effect on add-ons myself if I had saved the Hunter character, but it seemed useless at that time.

Any replies will be appreciated.

Thanks!

Gordon Houseman