- You are trying to resize a dynamic volume and leave unallocated space before it;
- There is no possibility to leave unallocated space before the volume: Unallocated space before volume field is grayed out and no marker is present for moving the volume layout:
This is by design.
Distribution of dynamic volumes on disks is calculated automatically. You can set Unallocated space before only for basic volumes.
Next update of the program will contain an appropriate warning with explanation of this behavior.