MDX Member formula too long but no error

Summary:

Hello all,

when I enter below's MDX member formula in EPCM ASO Cube, it validates successfully and also the refresh database is successful and works fine.

However, when I do not add /* */ to comment out a few lines of the code, the formula does not work correctly.

I tested the script by comment out /* */ lines in the upper (<> 0) and lower part (<> Missing) both work fine. However, when I do not comment out a few lines it does not work and never gives me the needed output (THEN).

Any ideas how to avoid this strange behavior?

Maybe you have an idea how to simplify / shorten the member formula.