I don't know how the selling actually works... I've tried to sell a few stocks this morning but it didn't go throuhg and just my luck the market dived!!!
jw
The share price is based on the real share price, so your sell orders will only go through if there's been some activity on the share. If there's no trading at all on the share your buy/sell orders won't be processed.
Also, if you specify a particular price to buy/sell (instead of choosing 'at market') your order won't be processed until the actual price occurs on the share market - for that to happen you'll need there to be some activity on the share in real life, otherwise the share price won't actually change.