I am having problems with accessing fields from the setting object from a portal. I've enabled the portal visitor access to this object and still i get an error. Is there a special setting for the settings object to make it a available for the portal? Thanks.
What exactly do you mean by "accessing" ? You can use Settings as template tokens, I believe.
I created a formula field in the settings object and enabled all permissions to the object, including portal visitor. Unfortunately when I use the template tokens, instead of giving me the value it computed for, it gives me
"ERROR: Error You do not have permission to perform this action (line #4) in formula:
341var rbv_api = new Packages.com.rb.core.services.api.ServerSideAPI(52358415, -1"
Please give View access to your object for "Query API" role.
Yes my object has this view access already, but still displays the error. Here's a similar error that we encountered. The first screenshot is from the portal side and the other is the permissions of the object. 
Hi Simone,
API on portal side works fine for my test environment. If you want me to help you further I'll need to look into your zone. There is nothing I can say at a moment.
You have clear references on line number (#4, #5) but you're not telling me what's on these lines. That would be helpful.