But in their Share Dealing Service document under term 20, there is this mentioned:
20.1. It may be possible for you to participate in a Corporate Action (including but not limited to dividends, voting rights, exercise of any conversion or subscription rights or other types of Corporate Actions attached to Investments we hold on your behalf). We will exercise our best efforts to inform you of such Corporate Actions but we cannot guarantee the timely delivery or correctness of any information provided by us with regards to such Corporate Actions. We are not obliged to but we may arrange for your participation in such Corporate Actions. We do not accept any liability for any actual or potential loss you may suffer if we are unable to facilitate your participation in any Corporate Action.
According to that term it is possible to participate in voting and other corporate events.