Out of curiosity, did Labour propose any renationalizations in 1992? Remember railways were still in public hands back then. Labour was more of a social democratic party in 1992 in the more traditional sense of the word, more supportive of regulation and progressive taxation than New Labour.
In short, your questions mostly hinge of whether Black Wednesday still happens. If it still takes place, they would probably need to make a few unpopular measures (at least in the short term) that might alienate them from the left. A lot would also ride on how it is spun. If Labour takes the fall, it would be catastrophic for them, seeing as they spent the past 13 years fighting to restore economic credibility, and now have lost it within months, seemingly confirming all the Tory rhetoric. A small majority or being dependent on the Lib Dems would also make it difficult for them to pass the constitutional reforms Blair managed.
The one thing they would have going for them is that the Tories would not be in a good place either, as whoever took over would have to deal with Maastricht, and the whole question of Europe, which Labour was comparatively united on by this point.
If they avoid Black Wednesday or pin it on the Tories, Kinnock would have a good shot at a second term, and his social democratic stance will be vindicated as it has now been proven it can lead Labour to power. With a smaller majority, Labour would probably be out next time though. Maybe they move to the right if they lose again after that, but 2008 might mean that whoever leads them ends up steering a reasonably left wing course anyway.If they lose power after one term, then something similar to New Labour would probably come into being in the next few years.