While working on an SAP enhancement project, my team created a customer screen where the development class was accidentally assigned to "$TMP." This meant we were unable to transport that screen.
We figured out a way to change the development class. If you have a similar problem and would like to use our workaround, follow these steps.
1. Call Transaction SE03: "Workbench Organizer: Tools."
2. Expand node: "Object directory."
3. Choose "Change object directory entries of objects."
4. Enter key fields R3TR FUGX and select line.
5. Enter (for example): XM02 as contents of the key field.
6. Start the selection.
7. Position your cursor on the selected entry: FUGX XM02.
8. Choose function: "Change object catalog entry."
9. Change and save the development class.
Thats it! Good luck.