convolution reverb in 4.25


i have run into some problems setting up reverb in unreal engine 4.25. Basically i have two problems.

First, i cant get to work the old reverb system to work anymore, where you place an audio volume in the scene and apply a reverb effect to the volume, which will trigger when the player camera enters the volume, but sadly not for me anymore. the reverb doesnt get applied to any sound i play inside the volume.

Secound, i tried to get the new convolution reverb system working, where you use audio impulse responses to create reverb effects, but im not that familiar with the new submix system and couldnt get that to work either. I saw two livestreams, where the devs showed the new sound system, that came with 4.25, but as a non audio expert i have difficulties to understand, how the new system works.

Is there anyone that ran into the same problem with the old system and knows how to fix it, or even better understands how the new system works and how to implement it correctly?

Thanks in regards