For the WAGO Devices and Libraries 2.0.5.6, install ONLY this package for Codesys 3.5.19.7.
It is HIGHLY recommended that 2.0.5.6 NOT be installed in previous versions of Codesys.
Why? There is a possibility of compiler errors that may arise from new 64-bit libraries (as noted in the link above).
Go ahead and keep your previous Codesys installs for FW26 and older. Use the “sandboxed” 3.5.19.7 for FW27 and newer.
Reply with any questions.