ID 320349 - NDK dynamic knobs: Creating dynamic LookupCurves_knobs leads to crash

Problem summary
Nuke crashes when mousing over the viewer using a dynamically created lookup curve

Customer reported version
nuke.10.0v5

Customer reported platform
n_a_linux

Steps to reproduce

1) Build attached plugin

2) Open attached Nuke script

3) Open properties of DynamicLookupSelect1 and mouse over image to correctly sample it.

4) Change curve type to "double" and back to "single"

5) Mousing over image causes crash.

Reproduced by support
This bug was confirmed by the developers

Expected behaviour
For Nuke to return samples when mousing over the viewer

Actual behaviour
Nuke crashed