Moving tables from one tab to another: I have already implemented single-screen transactions where I combine different tabs. Now I want to do the same for tables, i.e. move a table form one tab to another one. Is this possible?
Yes, you can "move" tables between tabs, but it will require some programming work:

Use the "Table" and "Column" commands in order to define a suitable table on the tab where you want to have the table. Fill in the values (if it is a "change" transaction) similarly to normal entry fields, but you need to scroll through the SAP table control in order to read all rows. For the scrolling technique, see our Tips&Tricks Nr.9.

The F11 update InputScript then requires the reverse action, i.e. filling the SAP table control from your own table. If adding and deleting table rows is supported in your own table, this requires some logic but can be done.