Now to respond to your questions:
Yes, as a director, you may be personally liable for the company's debts if you engaged in wrongful trading. However for this to happen, the company must first be put into liquidation (not receivership) as it it the liquidator of the company who may bring claims against you and your fellow directors under S. 214 of the Insolvency Act 1986.
On an application by the liquidator, the court has the power to declare that the directors are personally liable to make a contribution to the company’s assets in such amount that the court thinks proper, lifting the corporate veil of the company.
Under the Insolvency Act, directors incur personal liability for wrongful trading if, at some time before the commencement of the liquidation, they knew or ought to have concluded that there was no reasonable prospect of the company avoiding insolvent liquidation.
Your conduct will be assessed by reference to a reasonably diligent person having both the general knowledge, skill and experience reasonably expected of a person carrying out your duties as a director, and the general knowledge, skill and experience that you have.
You will have a good defence to a wrongful trading claim if you can show the court that you took every reasonable step to lessen the potential loss to the company’s creditors
So, yes, your personal assets and stocks are at risk and putting them in a company will not help as the court has wide powers to order you to pay up.
Hope this helps