To customize the element you need to follow these steps:

1. Add the block on your screen
2. Add the jsPDF script on the required script of the screen.
3. Select the requirements of the block. (here you will create the variables on the list of var)
4. Select the client actions to receive the data of the block.
5. The action of download will receive the global client action with the download logic.
6. The action of preview will receive the global client action with the preview logic.(To create preview you need create a container to receive the pdf preview and rename it to pass the id from parameter on cliente action preview)
7. The action of save will has the data of the textarea. You can do other things with data. Ex. save on database.
8. Remember that on the call of global client actions you have to do the FromXTo of the variables e use it like parameter.
9. Enjoy the component.