In general, no they are not allowed because of the rule you quoted. We are not a technical support site for other products (we don't allow things like "help, my DS broke").
So questions about why PO isn't working or how to fix something are not allowed. Don't worry about hiding old questions though. It might be worth taking one of the current questions and making a single question like "How can I fix problems with Pokemon Online?" that we can use in case of duplicates.
However, some PO questions are fine, if they actually relate to Pokemon. Like this one about Toxicroak because it's more about why you can't have a specific move combination.