Trying to make a 2D/3D Dynamic Pivot Door, but can´t make the 2D arc function properly

Hi. I´m trying to make a Dynamic 2D / 3D pivot door, but when setting the attributes to the opening arc’s LenX and LenY, I encounter a bug.
I’m trying to makek these attributes to be the lenght of the door, minus the position of the pivoting axis, on the Z axis.
It won’t accept the “minus” sign in the formula.

Do you know how to fix this? Thanks, I appreciate the help.
PIVOT DOOR.skp (5.9 MB)

the suffix of a number is causing the issue, so can use -1*2D!Pivot_2D instead of -2D!Pivot_2D, or change the parent name to TwoD or something without the numerical start


Thanks Pcmoor, you saved the day again.