so we made a kd/rta pattern that resembles predrills for lock dados, just simple 1/8 predrills and we have no problem anywhere with this pattern except for specifically the front right/left and back right/left dados on only the drawers
I'll link the following cabinet and the dbx.hsf file
The predrills show up and look ok until you nest and you can see that they disappear
one thing that i would note is that typically with lock dados there is a lock dado tenon in the construction parameters which is 11/16 which seems to just add interuption making the dado smaller so just for the sides because they could get pretty small (down to 3 inch high) we take away the interuption, and it's only the ones which have lock dado tenon set to 0 which have the issue
extra side note: this cabinet that i'm linking has another issue that i had to work around which just happened after the update to 6.2.10.3;
The stretcher for this sink base cabinet is rotated 90° and i couldnt flip it back to normal
so what i did was select instead of updown stretcher a frontback stretcher and used the stuck 90° "glitch" to my advantage and flipped the dado from front to back
and it didnt let me add the .ptn file for you guys to look at but u can recreate my predrills by making a 1/8 dia hole like this with the depth set as you see