Tabs sometimes forgotten

I notice that sometimes tabs are ignored or forgotten.
I can create a piece, add tabs… and its fine
but if i save it… open it another days… and try to carve
no tabs are cut
when I click on the object, tabs are not shown in the shape, but are still indicated in the setting,
if i increase it from 4-> 5 tabs re-appear

this also something happens when i rotate a piece that has tabs applied. they might get ignored or forgotten
I need to triple check before i cut if the tabs are still active…

I shouldnt have to do this. if i set it once it should remember my settings.
ruins several piece this way as at the end the piece got ripped out by the spindle.