I'm not too sure you can get any extra allowances/credits from the government when you start you're own company.As a director of the new company (I'm assuming you'll be setting up a limited company as opposed to a sole trade), you won't have to pay the same levels of PRSI that you were paying as an employee. You'll also have to make an annual return in a Form 12.You might be avail to claim back income tax paid over the last 5 years, through Seed Capital relief. Try the link below or contact the Revenue or Enterprise Ireland.
http://www.enterprise-ireland.com/Grow/Finance/Seed_Capital_Scheme.htm