[Solved][4.19] Material instance parameters does not work

Hi , I have a problem with 4.19 prev 5 , when i change parameter into a Material instance, nothing happens.
Same Material and Instance work fine in 4.18.

Activate Material Layering into Editor preferences make Instance Material parameters ineffective.
Disable Material Layering , and everthing back to normal.

This is really bad, makes preview 5 completely broken. Hope this will be fixed in preview 6 or i will need to go back to 4.18

Yes, this is fixed - we caught it internally just after Preview 5 went out. Keep an eye out for updates!

Preview 6 contains the fix for this issue, and is available now!

Well my terrain material instance isn’t saving all its data? when i close my project and reopen it parameters are lost, this was also the case when i updated from 4.18.2 it lost saved data.