The bridge is narrow because it is a compromise. I never wanted a bridge there buy sadly the AI could not handle the jump, as well that people wanted a failsafe mechanism, meaning the compromise was to have a narrow bridge to increase the likelihood of success :) the spawning is agreeable not good, but problematic to fix due to nature of AI sectors. Try using A class AIs seems to help a bit on problem.
Think I had to move he finish line away from the original start area due to the way the AI sectors work (not 100% sure on this as it has been some time), if I remember correct the game would just crash otherwise.

The spawn point does brake the map also for human players. If you are unlucky enough to spawn at that point you can get stuck because you are driving in the wrong direction no matter where you go. I dont know how to fix this but it needs to be fixed somehow.

Does it spawn you under the bridge and on the sector below? Probably right as the bridge in terms of AIs and sectors do not exist - they only see the surface the AI lines were attached to at track export time. Will try but no guarantee that it can be fixed. The AI sector system in Wreckfest is not always the ideal.

I experinced two things:

1. spawning under the bridge
2. spawning at the edge of the cliff right before the bridge but so much on the edge that its impossible to stay up

But i should add its also a while since i played this track the last time.

I don't doubt that you are correct, it probably is bugged :) I'll take a look at it and see if there is something to be done about it.