Cannot transfer unprotected tasks to CJ2M.

[Sergei Troizky 26]

I have a protected task in CJ2M, and have to download by tasks.
However, some unprotected task selection boxes for transfer are greyed, and cannot be selected,
while other unprotected tasks are selectable.
What may be a reason of not allowing unprotected task transfer.
All unprotected tasks were never protected. No UM protection.

Edited 7 Feb 2023 by Sergei Troizky