I am at the last steps in the process of making my witness operational again, this is the official re-announcement...
update:
I just wanted to report that v0.18.5's usage of the shared_memory file is much greater than it was in v0.18.2. The node is just synchronising still and it's currently up to late february. Where a witness only required 20gb for this file, now it needs at least 32Gb.