Hi,
I just tried this with the straight roller conveyor from the system assets and I didn't have any problems. I changed parameters, deleted conveyors, etc.
1) Place three roller conveyors.
2) Change the height of Conveyor 1 to 800 mm. All of the conveyors become 800 mm high.
3) Delete Conveyor 1.
4) Add a new conveyor connected to Conveyor 2. Conveyor 4 updates to 800 mm high.
5) Change the height of Conveyor 2 to 600 mm. All of the conveyors are 600 mm high.
6) Delete Conveyor 2.
7) Change the width of Conveyor 4 to 500 mm. Conveyor 3 doesn't change because the conveyors aren't connected.
8) Connect Conveyor 4 to Conveyor 3. The width of Conveyor 4 changes to match Conveyor 3.
9) Expand Conveyor 3 in the browser, and delete the Flush and 2 Mate constraints between the conveyors. These are the constraints created by the connection.
10) Change the width of Conveyor 4 to 500 mm again. Conveyor 3 doesn't update because the conveyors aren't connected.
11) Drag Conveyor 3 away and then connect it to Conveyor 4. Conveyor 3 updates to match the width of Conveyor 4.
There might be a problem with particular assets, or you might be doing something more complex.
Regards,
Loren