Pick your watch model. Select default layout. Now you can modify it and create your own.
Click on the field, you will see it underlined with red. Now you can change it's type under Field dropdown.
Click "Add Field" button, it will add a new field based on the Field type dropdown.
Click on the field you want to remove, make sure it's highlighted. Click "Remove Field" and see it removed.
When you are ready, click "Get Custom Layout" and see custom layout text generated in the area above. Click on it and copy the value into clipboard. Then insert the value into "Custom Layout" property in Digic Watch settings.
First of all select one of default layouts for your watch, generate text for it update your custom layout. If it doesn't help, please reinstall the DigicWatch and try again. Feel free to write me if nothing helps.