If a client's share capital is denominated in a currency other than GBP, Inform Direct supports this directly — currency is set at the point a share class is created.
When creating a new share class (for example via Share Classes > Share reorganisation > Create new share class, or during an allotment/incorporation), you'll be asked to select a Currency for that class from a dropdown, alongside the nominal value per share. The available currencies can be found in that dropdown.
See also: How do I create a new share class?