Re : Warning message during installation
I'm not much experienced about that, actually I never used hosting yet.
There is a permission issue about local.php, I guess this means apache can't read it. Does it exist? If not it may mean that fopen tries to create it and fails not having write permission to tiki/db/. Permissions should be handled by setup.sh, make sure you did this step right.
For the db connection, your DB user must have permission over the tiki DB...that's the only problem I can think of. If this doesn't help you make sure you came on #tikiwiki, it should be easier to try to solve that interactively.
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