I have both licenses for Eagle Layout Editor Version 4.15(Professional Version) and Eagle Layout Editor Version 5.7(Standard Edition).
I have a compatible issue between both versions.
I have created new package and overwrote the .lbr file using Eagle Version 5.7. Previously, the .lbr file was created under Version 4.15.
And I want to modify a .brd which was previously created in Version 4.15(Professional Version).
I have managed to place the new package in the .brd file under the Eagle Version 5.7.
However, I have an issue in moving and modifying the layout.
The error message is "The Standard edition of EAGLE can't perform the requested action! See Help for further details."
How do I able to know what type of errors and how should I go about to continue to work on it in Eagle Version 5.7?
If I need to work in Eagle Version 5.7, will I able to save the .brd and .lbr in a lower version so that I can also open the same files in Version 4.15.
If I need to work in Eagle Version 4.15, will I be able to retrieve the previous .lbr file in Version 4.15 to work on the .brd file in Eagle Version 4.15 since I have already started in Eagle Version 5.7?
Which is the best version to work on for .lbr and .brd files for my case?