This one of the 52 new Performances added with the firmware update. It is unlikely you had a problem with this
Performance previous to the update because it was not in the MODX until 2.00.

For example, if I use "ICE Theme" for example, I want to save some parameters. I opening PAD/CHOIR part and try to send RevSend parameter to zero, for example.

The amount of Reverb Send is *stored* in the SCENE. Data *stored* in a Scene snapshot will immediately be recalled when the Scene is recalled, overriding any change you made. There are four Scenes (selectable via the red Scene buttons 1-4). If you wish to review what is stored in each Scene you can as follows:

From the HOME screen tap “Scene”

Across the top you can see that Scene 1, 2, 3 and 4 have data stored.
MEMORY switches for Arp, Motion Seq, Mixing 1 and Mixing 2 are ON

Touch “Mixing 1” to review Rev Send, Var Send, Dry Level, Pan, and Volume

You can see that in each SCENE 1-4, Rev Send is stored at 45 for the Pad/Choir in PART 2
If you would like to change the setting to 0 change it in each Scene.
Changes made on the Scene screen are automatically stored with the Performance, when you [STORE] the Performance.

Touch “Mixing 2” to review the settings for each Scene 1-4 concerning Cutoff, Resonance, FEG Depth, MUTE status, Volume.
Again, all setting made on the Scene screen are immediately stored to the Scene, and when you STORE the whole Performance they become apart of your newly edited Performance.

Hope that helps.

Understood.
Thank you!