Bypass (shift-D) in Resolve doesn't update the image
When you use OFX plugin to connect with OmniScope and the plugin is applied in the node tree, hitting Shift-D (grade bypass) will bypass the OFX plugin as well and the results will not be displayed in OmniScope.
Please note, that the OFX plugin should be applied from the Edit Page rather than from the Color Page into the mini-timeline.
Fixing the playback in the Color Page
The above steps will cause the adjustment layer to be among your clips in the Color Page and trying to playback a sequence of clips will jump to the adjustment clip causing the whole track playback.
To fix it simply alt-click the track name in the mini-timeline in the color page. It will turn red and disappear from the clip list but the OFX connect plugin will remain active and OmniScope will continue receiving the frames.