Rewrote image capture subsystem for compliance with external/internal color capture.
SMART will default to BlockedEvents+CaptureEnable+GraphicsShown which is appropriate for RS safemode.
For something like OGL (care of external plugin) you want BockedEvents+CaptureDisabled.
Disabling capture removes the hacked buffer in the client canvas, making the client draw normally, but still blocks events (if SMART is enabled)