What preliminary tax for 2012?

I am filling out my FORM 11 on ROS for 2011 and on the final Tab, sign and submit I am prompted to enter my tax due for 2011 and also my Preliminary tax for 2012.
Can anybody tell me:

What are the panalties/implications of putting €0 into the Preliminary tax field even though I did trade in 2012.

I lost my building trade job as an employee in 2009 and was un-employed for 2 years before I decided to start operating as a sole trader myself as I could not find employment. I , like alot of unemployed people struggled and fell behind with general bank loans/credit union loans/car payments etc so I had a few debts at the time I became a sole trader.
The result of this is that I have not managed to save all my preliminary tax for 2012 while I was trying to juggle finances in my 1st year as a sole trader.

I have every intention of paying my tax and being fully tax compliant but I am just wondering what is the best to do here

Do i enter zero into the premlinary tax field?
Is it better to enter in my Preliminary tax amount I have calculated?
Can i enter it in but not pay it, or just give them what I have and make up the amount as soon as possible.
If I only give them what I can afford then I am assuming I can only enter in that amount that I have put by and that does not reflect the correct amount of Preliminary tax I have calculated is due for 2012.
Is there any use talking to the Revenue about this or is it just a case of pay up we don't care?

Any advice is greatly appreciated.
Regards, Conor.

This might be of use to you:
[broken link removed]

Sorry, I can't help you with an answer but I have a similar query with regards to the preliminary tax so hopefully you don't mind me piggy backing:

This is my second year filing the Form 11. I also went the sole trader route after being on the dole. Since the end of last year I have managed to take on a regular PAYE position which is also reflected in the statements on the form so I had partial sole trader income/partial PAYE income.

With regards to preliminary tax I have the following queries:
1) Where in the Form 11 can I deduct the preliminary tax I had already paid in October last year for 2011? I can't seem to find a field for this but would imagine that there should be a way to deduct that payment from my current liability for 2011.
2) Last year the summary for Form 11 gave a "Total Liability" field and a "Total Liability for 2011 Preliminary Tax Purposes" field. This year I only have a "Total Liability" field (no mention of a 2012 Preliminary calculation). I am suspecting that may be due to my having taken on PAYE employment but like the previous poster am not sure if I can therefore ignore this.

All help would be greatly appreciated.