If you have purchased the Professional version of My-CRM then yes you can run it on a network

Can I change to look and feel of my invoices?

Yes. You can change the look of any of the default quotations and invoices. This is done in Preferences

Can I stop other users from seeing my information?

Your system administrator will setup user access and permissions to who can see your data and who's data you can see

Can I user my CRM as a help desk?

The project module in My-CRM can be used to either track projects or helpdesk issues. To use it as a helpdesk tool. Check the "Use as a helpdesk" check box in preferences

I click on the help button but nothing happens

We are totally baffled by this. In most cases this works but we have heard in some instances nothing appears when the help button is clicked. As a get around whilst we solve this problem click on your windows start button and select programs\my-crm\My-CRM help