R works for me, and I have the same R extension as you (and the same KNIME version). I can’t really interpret that error message though.
Do other R nodes also fail? Can you execute the code within the configuration window? Line-by-line?
You could give this a shot and see if that fails as well:
Generate Sequence - Node Golf Version.knwf (22.7 KB)
(it’s from this thread)