Force the application to quit and restart. If the problems persists, please launch Disk Utility (on your 'Applications > Utilities') to check and repair permissions on your hard drive. You may have to reboot your computer.

Invoices are linked to one 'client' only. In order to add a new invoice, you first need to select the name on the left column of the software. To create an invoice, first select a name in the client list. Click on the newly available button in the top right : the invoice will be automatically added to database and displayed on the top table view of the application. As simple as it can be.

To add a new client, click on + in the bottom left of the window. A new form will prompt to fill the information you need. You can double-click to edit the information of a selected client.

Yes, simply click on the button + to add a new entry and click on 'Import' on the modal window to import an existing contact.

You can import and use any standard image file (png, jpg, gif, ...) to customize your logo. However, the logo size is determined by the invoice template and cannot be changed at the moment.

The software uses the system currency and languages of the OS by default.
Check System Preferences > Languages & Texts > Region to see which currency your system is using. You can however change the currency manually within the software by clicking on the 'Custom Print' at the bottom on the invoice form. A new panel will pop up where you can choose which currency to display on the toolbar.

The software create a .sqldata file in the /Users/ (your username) /Library/Containers/ com.exlibris.invoicing /Data/Documents/ folder. You can access it by simply clicking on the 'Show in Finder' button from the main menu Preferences > Data. You can copy this file for manual backup or transfer it to a new computer. Since OSX Maverick 10.9, it is also necessary to save two additionnal files with the extension .sqldata-shm and .sqldata-val, to avoid any data loss.