It is known and solvable issue
I'm currently using 2.8.4.0 version and it is ok, but kind of one-off
I just reinstall them after every use (which is hardly ever because all I need is cm11)
TWRP team said that
and here teamw.in/site/update/2015/02/12/twrp-2.8.5.0-released.html you can read that...