I have a track that was made before the final release and it uses a lot of these blocks, but works fine online. I haven't been following all of this closely, but I assume its only tracks that were made after release?

Have you reported this to Nadeo?

of course i have. After i reported it i started this post (both here as on maniaplanet forum) to tell the community about it.
And no, it hasn't always been buggy, so older tracks do work fine.

My not working track is from after the full release but before the last update.

After the last update I've removed some blocks, added some back, revalidated and computed shadows again but no succes online.

lol, i just drove your track.. you need to remove all ceiling blocks which would kill your tracks.
better wait about a week till new patch (just heard)

BLiNNeMaNS says:
lol, i just drove your track.. you need to remove all ceiling blocks which would kill your tracks.
better wait about a week till new patch (just heard)

Thanks for driving but indeed exactly that yes
I'm a patient guy so i'll sit out the next update aswell

This problem has been solved since the last server update (7-10-2011)
Thanxz for your investigations blinnemans