I am an australian citizen and I have a 2 year working visa (youth tier 5) for the UK. I have been traveling through Europe in countries that fall under the Schengen agreement, for almost 3 months, then I want to got to Scotland for 3 or 4 weeks and then return to Europe (Portugal) for 2 months or longer. Is this possible? Does having the UK working visa give me rights of a UK resident regarding length of stay in Europe?
The answer is: No.
You're still subject of 90 in 180 day stay even if you have a British Type 5 visa.
You can refer to requirements posted by Austria as a guide.