There are a few ways to link a SceetoBot to any of your favorite studies.
The quickest way is to use the Sierra Chart study, 'Color Bar Based on Alert Condition' as an intermediary link.
Use the alert tab in the study, 'Color Bar Based on Alert Condition' to create an output to link back to your SceetoBot when your signal condition is True.
Use the Signal linking within your SceetoBot to create a signal button the bot's Designer Panel.
More information on linking within the SceetoBot study can be found here.
Sample MACD Crossover study signal can be downloaded here.