Hi @ABaier ,
could it be, that this question is related to this one:
https://forum.commonvisionblox.com/t/gevserver-changing-image-length/1850/4
What I understand is: You want to change the ImagerLength node (or some similar Node) but you cant, as the Node ist currently ReadOnly.
The reason it is ReadOnly is very likely because you have an active Grab going on.
So the only way to change the desired Node actually is to stop the Grab bevore trying to change it.