This bug is only visible when caching is enabled (tests/round.php fails), since the database is (apparently) case insensitive and the cache is case sensitive.

All urls are normalized so admin/runda/tEst_Round becomes admin/runda/test_round. The round is stored in the database with id tEst_Round.  The parameter cache uses id tEst_Round to get round parameters, but it uses test_round to update them, so the parameter cache is never updated the right way.

I think the best solution is to just make all round ids lower case (this patch does that) to avoid problems somebody may have with normalized urls in the future.