Projects have a limited amount of elements to use. Elements like sensor, actuators and services are being counted and there is a limit for that
Logic gates, such as: AND, OR, NAND and COMBO are not counted.
The number of elements you can use in a project you can find on the Account details page of your Conrad Connect account.
If you want to create projects with more elements, you can subscribe for our 'Enhanced Projects Premium Service' in the 'Addons & Services' section.